IMPROVEMENTS IN CENTRIFUGAL SIFTING-MACHINES
Year: 1884

page_text: I, JOHN HENRY JOHNSON, of 47 Lincoln's Inn Fields, in the county of Middlesex,
Gentleman,.do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN CENTRIFUGAL SIFTING-MACHINES," a communication to me from abroad by
Gustav Daverio, of Zürich, Switzerland, Engineer, to be as follows:-
This invention relates to Centrifugal Sifting-machines for dressing flour and other
ground materials, and the improvements.consist, firstly, in the particular manner
of dividing a centrifugal sifter with one cylinder into two sections, or a like
apparatus with two superposed cylinders into four sections, adapted to operate
independently of each other; secondly, in the means employed for closing the slits
between the cylinders and the walls of the boxes in which they are contained, and
thirdly, in the manner of mounting the shaft of the beaters in bearings and the
cylinder on rollers, so that both, the bearings and the rollers are adjustable by
hand, and that, besides, the bearings will adjust themselves automatically to
the shaft.
For dividing a sifting-machine with one cylinder into two sections adapted to
sift 'two distinct quantities of grist, the gauze covering of the cylinder is left away.
upon the middle part of the latter, and in the centre of this uncovered part is fixed
to the frame of the cylinder a round disk, while the box of the apparatus is
vertically divided by a partition-wall, cut out circularly according to the form of
the said disk, and arranged in the same plane therewith. The spaces into which
the sifted products fall, are separated from those for the residues by two other
partition-walls and by rings on the cylinder-frame to which the gauze is attached.
The sifted products are transported by means of a creeper, having on one half a
right-hand thread, and on the other half a left-hand thread; towards the discharge-
apertures at the ends of the apparatus. The residues are conveyed by blades fixed
on the periphery of the cylinder, or in other suitable manner, to lateral apertures
in the box.
It will be readily understood that two machines of this description may be
combined in a common-box; a machine with four sections operating independently
of each other being thus produced.
•

page_text: The slits between the aforesaid partition-walls on one hand; and the disk as well
as the rings of the cylinder on the other hand, may be closed in any suitable and
known manner; but preferably I employ for this purpose packings made of cords.
of hemp or other like material, which are kept in their place, opposite to the edges
of the rotating parts, by retaining-rings of metal or papier-maché, screwed to the
partition-walls and having grooves to receive the cords. Like packings serve to
close the slits between the outer ends of the cylinder and the end-walls of the box
and parts connected therewith. The grooves for the. cords are, however, not
necessarily required to be in the said retaining-rings; they may also be formed in
the walls and other, parts of the box, or even in the moving parts, the rings being
then arranged to overlap the grooves so as to hold the cords, or the grooves are
formed by the walls and other parts in combination with the rings. In some cases
the retaining-rings may be omitted, as for instance when, the groove is on the
outer periphery of a part. Moreover, two slits which are in proximity of each
other, may be closed by a single cord and one ring, the. former being made flat, so
as to cover both slits. Such packings may also be used in undivided machines.
For imparting to the bearings of the beater-shaft the desirable amount of
self-adjustability, so that they may perfectly accommodate themselves to the shaft,
each bearing is pivoted on pins secured to a ring, which is free to oscillate on fixed
pins, arranged at a right angle to the former. Moreover, in order to allow either
bearing to be adjusted bodily in vertical as well as in horizontal sense by hand, the
said pins are screwed respectively into the ring and into arms attached to a
stationary part of the apparatus, so that by turning them, the position of the
bearing will be altered. Besides, the said arms may be made adjustable lengthwise
in respect to the shaft by being inserted into suitable holes and secured by
set-screws..
The cylinder is mounted at either end with its naves on rollers, rotating on pins,
having stems that are eccentric to their body, and fixed with these stems, and by
means of nuts, in the plates closing the apparatus at the ends. By slackening the
nuts and turning the pins, the rollers, and, in consequence, the cylinder" will be
raised or lowered, or shifted to the right or left.
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page_text: I, JOHN HENRY JOHNSON of 47 Lincolns Inn Fields, in the county of Middlesex,
Gentleman, do hereby declare the nature of the said invention for "IMPROVEMENTS
IN CENTRIFUGAL SIFTING-MACHINES" and in what manner the same is to be
performed, as communicated to me from abroad by Gustav Daverio, of Zurich;
Switzerland, Engineer, to be particularly described in and by the following
statement:-
This invention relates to Centrifugal Sifting-machines for dressing flour and
other ground materials, and the improvements consist, firstly, in the particular
manner of dividing a centrifugal sifter with one cylinder into two sections, or a
like apparatus with two superposed cylinders into four sections, adapted to operate
independently of each other; secondly, in the means employed for closing the slits
between the cylinders' and the walls of the boxes in which they are contained,
and thirdly, in the manner of mounting the shaft of the beaters in bearings and
the cylinder on rollers, so that both the bearings and the rollers are adjustablo
by hand, and that, besides, the bearings will adjust themselves automatically
to the shaft.
On the annexed sheet of drawings Fig: 1 represents in longitudinal and vertical
section a sifting-machine with one cylinder divided in two sections. Fig: 2 is a
front view, and Fig: 3 a transverse section of the same apparatus. Fig: 4 shows
to a larger scale the middle part of Fig: 1, and Fig: a transverse section
corresponding thereto. Fig: 6 is a longitudinal section of the outlet end of an
undivided sifting-machine. Fig: 7 is a longitudinal section, Fig: 8 a front view
and Fig: 9 a sectional plan of either end of the sifter Figs. 1 and 2, while Fig: 10
shows the outlet-end of the sifter Fig: 6; the Figures 7 to 10 being drawn to the
same scale as Figs: 4 and 5. Fig: 4 finally is a section of a part in detail.
The sifting-machine shown by Figs 1 to 5, and in which the cylinder is divided
into two sections, is adapted to sift simultaneously two distinct quantities of grist,
whether of the same or of different kind, the sifted products as well as the residues
issuing from the machine each by a special conduct. For this purpose the gauze'
covering of the cylinder is left away upon the middle part of the latter, and in the
centre of the uncovered portion is fixed to the frame of the cylinder a round disk b,
preferably of wood, while the box of the apparatus is vertically divided by a
partition-wall b' cut out circularly according to the form of the said disk and arranged
in the same plane therewith. The spaces or compartments c into which the sifted
products fall, are separated from those for the residues by the two partition-walls b³,
and by wooden rings k on the cylinder-frame, to which the gauze is attached.
.
On the circumference of each cylinder are fixed longitudinal blades d, which
scrape the sifted grist together and deliver it to the two creepers or conveyors e,
having a common axle, and one of which is provided with a right-hand and the
other with a left-hand thread. These conveyors transport the grist from the two
sections of the sifter separately to the discharge-orifices f and f¹. The residues,
which fall into the compartments c³, are collected and conveyed transversely along
the bottom of either compartment c¹ (which passes away over the creeper) towards
the discharge-orifices f³.

page_text: The apparatus shown by Fig: 1 is driven by the pulley g keyed on the shaft y
of the beaters A. By means of chains running over sprocket-wheels h h, motion
is communicated to the conveyors e. The cylinder, finally, is put in rotation by a
chain passing over the sprocket-wheel ¹ fixed on the conveyor-shaft, and over the
teeth on the head of the cylinder.
It will be feadily understood that the described arrangement of a centrifugal
sifter with divided cylinders may also be applied to like machines with two divided
cylinders, disposed one above the other in a box comprising two pairs of superposed
sections; a machine with four sections-operating independently of each other, being
thus produced. The rotation of the beater-shaft of the first cylinder may, in this
case, be transmitted to the corresponding shaft of the second cylinder by pulleys
fixed on these shafts and a strap.
The slits between the partition-walls b' and 62 on one hand, and the disk bas
well as the rings on the other hand, may be tightened in any suitable and known
manner; but preferably the inventor employs for this purpose packings consisting
in cords, Figs 4 and 4*, made of hemp or other similar fibrous material, and
which are kept in their place opposite to the edges of the rotating parts by
retaining-rings m of metal or papier-maché, screwed to the partition-walls, and
having grooves to receive the cords.
At their feeding-ends the two sections of the cylinder are partly closed by
annular plates ; as shown to best advantage by Fig: 7; and these ends, which
are fitted with wooden rings ¹, rotate within corresponding apertures in the
end-walls b of the sifter-box. The slits between the walls 63 and the rings ¹ are
tightened in a like manner as described, by cords P, Fig: 7, and rings m¹ fixed to
the walls 6. The central aperture of each of the said plates t¹ is closed by a
stationary plate carying the feed-inlet, and tightened against t¹ by a cord l
inserted into a groove at the edge of the periphery of x.
By means of the said cords the machine is rendered perfectly tight against any
loss of flour; the frictional resistance which they cause, is insignificant, they do
not require to be put into their place until the machine has been completely erected
on the spot where it is to work, and they may easily be removed and renewed.
In the case of an undivided cylinder, the end of the machine at which the
residues issue, is closed in the manner represented by Figs. 6 and 10, by means of
a plate, having the opening or spout f, and the cylinder is fitted with a wooden
ring, similar to the one at the other end of the cylinder. This ring also
projects with its edge into the circular aperture of the corresponding wall b³, and
the plate is provided opposite to the ring with a rim x. In this manner the
space within the cylinder and the one surrounding it, are not only closed towards
the outside, but they are also separated from each other, and inoreover, the slits
between the pieces thus arranged may be tightened by a single flat cord land
one ring m¹:
For conveying the residues of the sifting-process to the aperture or spout f*,
plates d' are fixed to the arms of the cylinder. The spout may be arranged at
any desired point of the lower half of the space c² formed by the plate a¹, and
within which the residues collect.
In centrifugal sifters, and especially in large apparatuses of this kind it is of
importance that the bearings of the beater shaft be so constructed as that they
may accommodate themselves automatically to the shaft, and that these bearings
as well as those of the cylinder be provided with means for allowing them to be
fitted up with facility, and to be adjusted with precision. In view hereof these
parts are arranged as follows:
Each bearing n see Figs 7 to 10, is pivoted on vertical pins p screwed into a
ring q, which in its turn is pivoted on horizontal pins p¹, screwed into the arms r,
the latter being attached, to the plate x, respectively, which is fixed to the box
of the apparatus. The bearing is thus free to oscillate in all directions, and, by
turning the pins p and p¹; the position of the bearing may be altered as well
horizontally as vertically. The arms are made adjustable lengthwise in respect

page_text: to the shaft y by being inserted into sockets 8-on the plates and x³, and secured by
set screws p². The upper screw p may be employed for carrying an oil-cup, the
screw being perforated lengthwise for conducting the oil to the shaft.
The cylinder A¹ is mounted with its naves t on rollers u, rotating on pins v,
having stems w that are eccentric to their body. By means of these stems
and nuts Z at the ends thereof, the pins v are fixed in sockets on the plate x,
respectively ; but, after the nuts have been slackened, the pins may be turned
by a key applied to the square part w² of the stems. This arrangement allows the
rollers to be adjusted higher or lower, or towards either side, and the position of
the cylinder to be regulated accordingly. The pins are perforated lengthwise
and transversely, and to the end of their stems oil-cups are screwed for the
lubrification of the rollers.
Having now particularly described and ascertained the nature of the said.
invention, and in what manner the same is to be performed, as communicated to
me by my correspondent, I declare that what I claim is:
1. In centrifugal sifting-machines the arrangement according to which the
cylinder and the box thereof, or each of two superposed cylinders and of the
respective compartiments of the box, are divided into two sections, adapted to
operate independently of each other; the sections being separated from each other
by means of the disk b, the rings and the partition-walls b¹ and 6², while the
shits between the stationary parts b₁ and b, and the rotating parts b. and k, are
tightened against the passage of flour, substantially as and for the purpose
described.
2. In centrifugal sifting-machines the inethod of tightening the slits between
the cylinder and appertaining parts on one hand, and the walls of the box as well
as the head-plates x, respectively on the other hand, by means of cords. kept in
their place by rings, such as m and m¹, or inserted into a groove on the stationary
part, as for instance the plate, substantially as described.
3: In the said machines, the system of mounting the beater-shaft y in bearings n,
which are free to pivot, and which may be adjusted in two directions by means of
the screwthreaded pivots p and p¹ and the ring 9; the latter being moreover
adjustable lengthwise to the shaft, substantially as and for the purpose specified.
4. The arrangement consisting in mounting the cylinder with its nave on
rollers u, carried by pins having eccentric stems w, which, when being turned in
their sockets, will cause the pins and the rollers to be shifted radially, substantially
as described and for the purpose set forth.
Dated Lin thistonth dose of I. 100-