Improvements in Apparatus for Sieving or Purifying Grain, Middlings, and other Mixed Finely Divided Material.
Year: 1890

page_text: Date of Application, 9th Dec., 1890
Complete Specification Left, 9th Sept., 1891-Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Sieving or Purifying Grain,
Middlings, and other Mixed Finely Divided Material.
I JOHN MOODY EMERSON of 11 Sandown Terrace, Wavertree in the County of
Lancaster do hereby declare the nature of this invention to be as follows:-
This invention has for its object an arrangement of purifier or sieving apparatus
in which the new system of working with a throttled draught and after expansion
over channels is carried out with the greatest efficiency.
In order to increase the force of the draught in the live portions and have dead
portions of the sieve immediately under the troughs I cement to the sieve strips of
macintosh or other airproof material or even solid bars or laths, or I may paint
them over with a tough composition so that no blast can come through these points
thus concentrating all the work on the useful portion. Secondly, I place my
troughs, when they are longitudinal, right on the surface of the sieve fastening the
sieve to them when necessary or if the sieve has to work independently of the
If the troughs
troughs I place the troughs as close to the sieve as is practicable.
touch the sieve all along there is no need for the air proof strips as the trough-
bottoms which are flat themselves form dead spaces in the silk.
The great complaint of millers with this modern system of settling troughs is
that they hide the silk. In order to overcome this and also to regulate the
apparatus with the greatest nicety to the various kinds of work it has to perform,
and also to get the greatest throttling effect without the disagreeable result of the
fluff, chaff or bran bridging between the various troughs, I form the trough sides
hinged to their bases and every alternate side hinged to a bar at right angles
thereto, the other alternate sides being hinged to a second bar. If these two bars
project through the side or end of the machine, by regulating them by hand or with
a screw any required opening can be obtained while by pushing them far over on
to the trough, the operator will have an unrestricted view of the operative surface
of the silk.
In some
Furthermore if an automatic or other shaking arrangement be connected with the
two rods so that the rods can be shook at intervals, the sides of the various troughs
can be brought very close to each other without fear of trouble from bridging as
the bridges are instantly broken every time the rods are agitated.
machines at the present time arrangements are made whereby there shall be a
tolerably large area of blast at the upper part of the sieve, less at the middle part,
and very small at the lower. This has been accomplished by making the sieves of
tapering width. The result of this, however, has been that the material collects in
long ridges by the sides of the troughs.
Now in order to avoid this I form my troughs of two, three or more lengths each
parallel throughout and with an abrupt but slightly oblique shoulder between each.
This shoulder at once throws the accumulation off into the middle of the channel
and prevents the formation of these ridges so deleterious to the accurate working
of the machine. In place of reducing the troughs in width they can be increased
in number if desired.
Further as the material that falls into the troughs in the upper part is different
to that which falls into the lower part of the troughs I may arrange to have each
of the lengths of trough emptied into a trough transverse to them which is
continuously emptied by means of a travelling brush or equivalent mechanism to
the sides.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Sleving or Purifying Grain,
Middlings, and other Mixed Finely Divided Material.
I, JOHN MOODY EMERSON, of 11, Sandown Terrace, Wavertree, in the County
of Lancaster, Engineer 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 has for its object an arrangement of purifier or sieving apparatus
in which the new system of working with a throttled draught and after expansion
over channels is carried out with the greatest efficiency.
The invention may be described with reference to the accompanying drawings in
which
Figure 1 is a plan of the sieve with its series of dust collecting troughs,
Figure 2 is a transverse section through a few of the troughs and the adjacent
portions of the sieve, and
Figure 3 is a similar section showing the parts in a different position.
In order to increase the force of the draught in the live portions and to have dead
portions of the sieve immediately under the troughs, Firstly I cement to the sieve,
strips of macintosh or other air-proof material or even solid bars or laths. Or, I
may paint them over with a tough composition so that no blast can come through
these parts.
Thus the work is all concentrated on the useful or live portions of
the sieve.
Secondly, I place my troughs A when they are longitudinal, right on the surface
of the sieve B, as seen in Figures 2 and 3, fastening the sieve to them when
necessary; or if the sieve has to work independently of the troughs, I place the
latter as close to the sieve as is practicable. If the troughs touch the sieve all
along there is no need for the air-proof strips aforesaid, as the trough bottoms,
which are in this case flat themselves form dead spaces in the silk.
The great complaint of millers with this modern system of settling troughs is
that the troughs hide the silk. In order to overcome this objection and also to
regulate the apparatus with the greatest nicety to the various kinds of work it has
to perform, and also to get the greatest throttling effect without the disagreeable
result of the fluff, chaff or bran "bridging" between the various troughs, I form
the trough sides A hinged to their bases e as in Figures 2 and 3, and I hinge every
alternate side to a bar D at right angles theretc, the other alternate sides being
hinged to a second bar d. If these two bars project through the side or end of the
machine, any required opening may be obtained by regulating the bars by hand or
with a screw, while by pushing them right over as in Figure 3, the operator will
have an unrestricted view of the operative surface of the silk. Furthermore, if an
automatic or other shaking arrangement be connected with one or both of the rods,
so that the sides of the troughs connected therewith may be shaken at intervals, the
opposing sides of the various troughs can be brought very close to each other
without fear of trouble from bridging as any accumulation of material between the
troughs is instantly shaken off every time the said sides are agitated.
In some machines at the present time, arrangements are made whereby there shall
be a tolerably large area of blast at the upper part of the sieve, less at the middle
part, and a very small area at the lower. This has been accomplished in some cases
by making the sieves of tapering width. The result of this, however, has been that
the material collects in long ridges by the sides of the troughs which are located
one on each side of the sieve.
Now in order to avoid this accumulation and at the same time to obtain the
advantages of the decrease in the sieve area from head to tail, I form my troughs of
two, three or more lengths a¹ a² a Figure 1, each parallel throughout and with an
abrupt but slightly oblique shoulder a₁ between each. This shoulder at once throws

page_text: any material which tends to accumulate thereat off into the middle of the channel
between the adjacent troughs and prevents the formation of the aforesaid ridges
which are so deleterious to the efficient working of the machine. In place of
increasing the width of the troughs from head to tail of the sieve they may be
increased in number if desired.
Further as the material that falls into the troughs at the upper part of the sieve
is different from that which falls into them at the lower part of the sieve I may
arrange to have each of the lengths of troughs a¹ a³ a³ emptied into a trough E
transverse to them and continuously emptied by means of a travelling brush or
equivalent mechanism discharging at the side or sides of the sieve as at F.
One advantage of my arrangement of adjustable sides to the troughs is that it
enables me when working on very coarse material to open the wings or sides till
they nearly or quite touch each other over the troughs or their narrower parts, so
that the opening at the top of said wings is greater than at the bottom, or silk
surface. In this way I have less intensity of air current a few inches (more or
less) above the silk than immediately on its surface, the result being that while the
air current through the meshes of the silk may be strong enough to prevent any
particle of impurity from passing through the mesh, and may be also strong enough
to lift good material off the sieve surface yet the expansion of air towards the top
of the sides or wings of the channels and the consequent lessening of its lifting
power, allows the good or heavier particles to again fall towards the silk, and
subjects it to a more continuous lifting and falling action. In this way all my
product is under the action (and a more severe action) of the air current and
consequently gets a better purification while there is less possibility of any food
product being carried away and wasted.
The light material (impurities) is gradually floated towards the tail of sieve
(some of it being caught in the channels) and may be either tailed over end of sieve
or lifted away by the use of a stronger current of air towards tail of sieve.
I am enabled to use a coarser mesh in my operations as the purification is not so
much a sieving as a specific gravity and air action.
When the sides are set back till they touch over the troughs, all the impurities
are floated towards tail of machine (that is all such as are not carried into fan and
depositing chambers in top of machine). The undersides of the transverse troughs E
are placed at a sufficient distance from the sieve surface to permit of the free
passage of the material below them. When using these troughs E, the longitudinal
troughs A may be placed on the sieve or a short distance above it."
In either case,
however, the bottoms of the interiors of the troughs are at such relative heights that
the material collected in each longitudinal set may freely discharge itself into its
transverse trough.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In apparatus of the kind described, a series of dust collecting troughs arranged
above the vibrating sieve, having their sides adjustable in slope and connected with
mechanism whereby the alternate sides may be simultaneously shaken, moved aside
or adjusted in angle, substantially as described.
2. In apparatus for sieving or purifying grain or other granular substances, the
combination of troughs placed above the sieve and clear of the same with
impervious strips in the sieve placed immediately below the troughs whereby while
all the effective current is utilised on the silk between the troughs, free passage for
the material is obtained to spread all over the sieve.
3. In an apparatus of the kind described, a series of dust collecting troughs
arranged longitudinally above the vibrating sieve and formed of successive sections
of uniform width throughout, but each section greater in width than the previous
section from the head to the tail of the sieve, substantially as and for the purpose
described.

page_text: 4. An arrangement of troughs over a sieve with the sides sloping inward or
capable of being turned to slope inward whereby a lessening of current takes place
between the troughs as and for the purposes described.
5. In an apparatus of the kind described, the improved arrangement of longi-
tudinal and transverse dust collecting troughs taken as a whole, substantially as and
for the purposes described, and as illustrated in Figure 1:
Dated this 8th day of September 1891.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents.