Improvements in Middlings Purifiers.
Year: 1894

page_text: Date of Application, 18th Sept., 1894
Complete Specification Left. 18th June, 1895-Accepted, 20th July, 1895
PROVISIONAL STETICATION.
Improvements in Middlings Purifiers.
I, THOMAS FREDERICK' HIND and' ROBERT LUND, both of the' Atlas Works,
Preston, in the County of Lancaster, Flour Mill Engineers, do hereby declare the
nature of this invention-to be as follows:-
This invention relates to improvements in middlings purifiers of the vibrating
sieve type and has for its object to provide an improved: method of separating the
finer particles of the material under treatment and also to provide facilities for
inspecting the upper surface of the silks or sieves of such machines. In carrying
out our said invention we employ a stationary grid-as distinguished from a
travelling grid of the endless or rotating chain kind-but we so arrange it that it
may be hoisted or lifted away from the silks so as to leave the same visible for
inspection. The hoisting mechanism may conveniently consist of chains or bands
passing upwards from each end of the grid over pulleys and under and over another
central pulley whose rotation by means of a suitable handle winds or unwinds each
opposite set of chains or bands simultaneously. The grid we employ consists of an
outer frame with cross bars at suitable.distances from each other so as to allow of.
the usual suction draught or air current between them-the said cross bars being
preferably in the form of sheet metal troughs having a baffle plate so formed and
placed over the upper edges of each adjoining pair of the troughs as to interrupt
the upward current of the air and to.deflect it downwardly and thereby to direct
the finer particles of the material under treatment into the said sheet metal troughs.
The troughs may be arranged either transversely or lengthwise of the machine-in
either case each trough is provided with one or more brushes, carried on an endless
band the said brush or brushes sweeping out of the trough below the material
collected therein and in the case of the transverse troughs depositing the material
upon a side tray and in that of the longitudinal troughs discharging it at the tail
end of the.machine. The rollers carrying the endless brush bands are mounted on
stands on the framing of the grids so as to move up. and down therewith and the.
required rotation may be imparted thereto through the medium of endless band
and pulley mechanism. Whether the troughs be arranged transversely or
longitudinally we prefer to employ side trays that is to say one on each side of
the.grid.
$
Improvements in Middlings Purifiers.
We, THOMAS FREDERICK HIND and ROBERT LUND, both of the Atlas Works,
Preston, in the County of Lancaster, Flour Mill 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 improvements in middlings purifiers of the vibrating
.

page_text: sieve type and has for its object to provide an improved method of separating the
finer particles of the material under treatment and also to provide facilities for
inspecting the upper surface of the silks or sieves of such machines. In carrying
out our said invention we employ a stationary grid-as distinguished from a
travelling grid of the endless or rotating chain kind-but we so arrange it that it
may be hoisted or lifted away from the silks so as to leave the same visible for
inspection. The hoisting mechanism may conveniently consist of chains or bands
passing upwards from each end of the grid over pulleys and under and over another
central pulley whose rotation by means of a suitable handle winds or unwinds each
opposite set of chains or bands simultaneously. The grid we employ consists of an
outer frame with cross bars at suitable distances from each other so as to allow of
the usual suction draught or air current between them-the said cross bars being
preferably in the form of sheet metal troughs having a baffle plate so formed and
placed over the upper edges of each adjoining pair of the troughs as to interrupt
the upward current of the air and to deflect it downwardly and thereby to direct the
finer particles of the material under treatment into the said sheet metal troughs.
The troughs may be arranged either transversely or lengthwise of the machine-in
either case each trough is provided with one or more brushes carried on an endless
band the said brush or brushes sweeping out of the trough below the material
collected therein and in the case of the transverse troughs depositing the material
upon a side tray and in that of the longitudinal troughs discharging it at the tail
end of the machine. The rollers carrying the endless brush bands are mounted on
stands on the framing of the grid so as to move up and down therewith and the
required rotation may be imparted thereto through the medium of endless band
and pulley mechanism. Whether the troughs be arranged transversely or
longitudinally we prefer to employ side trays that is to say one on each side of the
grid.
In the accompanying drawings,
Fig. 1 is a sectional side view illustrating the arrangement of our improved
stationary grid, the silk or sieve, and the mechanism for hoisting or lifting up the
grid so as to leave the silk or sieve visible for inspection.
Fig. 2 is a detail sectional view (drawn to a larger scale) of the sheet metal
troughs and baffle plates or deflectors forming the improved grid.
Fig. 3 is a cross sectional view and
Fig. 4 a side view showing more particularly details of the hoisting mechanism
and also of the brush mechanism for sweeping out on to the side trays the material
collected or deposited in the trough.
Fig. 5 is a plan view of the improved grid.
a represents a silk or sieve of the ordinary type and bb the side trays leading to
the outlet c. The improved grid consists of an outer frame d with cross bars in the
form of sheet metal troughs e e and of upper or surmounting baffle plates or
deflectors ff which-as the finer particles of the material under treatment are
lifted by the upward air current from the surface of the silk a-are deflected
downwardly and deposited in the troughs e e. In the drawings the troughs e e are
shewn arranged transversely and when so arranged we employ a series of brushes
projecting downwardly from a barg each of the troughs e e being provided with
a separate brush the two extremities of the bar g being supported on screw nuts
which traverse backwards and forwards on the double reversely threaded screws i i
which are in gear with each other-so as to rotate simultaneously-through the
medium of an endless pitch chain ; and the chain wheels k k. The bearings ll
which carry the screws ii are fastened to the grid frame d d and each end of the
screw shafts i i passes through an additional bearing m held in the vertical guide
groove n so as to slide therein and suspended from the chains or bands o o¹ passing
upwards from each end of the grid (see Fig. 1) over pulleys pr and under
and over the central pulley 9 which may be caused to wind and unwind the
chains oo when it is desired to raise or lower the grid-by means of the handle v.
At Figs. 3 and 4 the shaft r through bevel gear s drives the vertical shaft t and

page_text: through bevel gear uu¹ the screw shafts ii the said vertical shaft t being formed with
a key way or slot and a key or feather within its bevel wheel u so that the latter may
readily slide up and down thereon during the operation of the hoisting mechanism
as will be readily understood.
If the grid be formed of longitudinally disposed troughs and deflectors then the
brushes h may be arranged on an endless band passing over suitable rollers mounted
in bearings rising at each end from the framing of the grid so as to rise and fall
therewith.
In lieu of brushes formed of bristles or the like scrapers formed of wood, sheet
metal, or other flexible material may be employed.
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 a middlings purifier the use or employment of a stationary grid consisting
essentially of cross bars in the form of troughs and surmounting baffle plates or
deflectors arranged substantially as described and shewn in the drawings.
2. In a middlings purifier the combination with a grid of the kind referred to in
Claim 1 of hoisting mechanism for raising and lowering the said grid substantially
as described and shewn in the drawings for the purpose specified.
3. In a middlings purifier the combination with a grid of the kind referred to in
Claim 1 and hoisting mechanism for raising and lowering the said grid of apparatus
for brushing or sweeping out the material collected or deposited in the troughs of
the said grid substantially as described and shewn in the drawings.
|Dated this 18th day of June 1895.
Dated this Tŏth day of June 1895.
For the Applicant,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.