IMPROVEMENTS IN CENTRIFUGAL MACHINES AND IN THE MANUFACTURE OF SUGAR THEREIN
Year: 1883

page_text: LETTERS PATENT to Alfred George Brookes of N° 59 Chancery Lane in the
County of Middlesex Patent Agent for an Invention of "IMPROVEMENTS
IN CENTRIFUGAL MACHINES AND IN THE MANUFACTURE OF SUGAR THEREIN
Communicated to him from abroad by David M.Colley Weston of Boston,
County of Suffolk and State of Massachusetts in the United States of
America.
COMPLETE SPECIFICATION filed by the said Alfred George Brookes at the
Office of the Commissioners of Patents on the 17th April 1883.
"
ALFRED GEORGE BROOKES of N° 59. Chancery Lane in the County of Middlesex
Patent Agent "IMPROVEMENTS IN CENTRIFUGAL MACHINES AND IN THE MANU-
FACTURE OF SUGAR THEREIN Communicated to ine from abroad by David
McColley Weston of Boston County of Suffolk and State of Massachusetts in the
United States of America
My invention consists essentially in the combination with a revolving cylinder
of a centrifugal machine, with an impervious pan-like charger located within it to
receive the sirupy mass or charge, hold it and when the machine is in motion
discharge the charge outwardly against the wall of the cylinder, as will be
hereinafter described.
Also, in a rotating shaft, and a connected centrally impervious pan-like charger
combined with an outer perforated cylinder, and with arms to unite the said
charger with the said cylinder between its ends as described, so as to rotate the
cylinder in unison with the charger as and for the purpose hereinafter set forth.
Also in a centrifugal machine, a cylinder having its lower end open or
unobstructed at its centre, combined with a plow adapted to be entered into the
sugar wall, and with means to operate the said plow through the bottom of the
said cylinder as will be described.
Also in that improvement in the art or method of purging sugar which consists
in supplying the material or charge into an impervious charger while at rest and
occupying a central position with relation to the cylinder, and discharging the
same in volume from the charger into the cylinder over the top of the charger
after the same has had its speed raised sufficiently to force the charge outwardly
therefrom thereby immediately spreading the charge to form a wall as will be
described.

page_text: Also that improvement in the art or method of purging sugar which consists in
supplying the charger of the machine with a charge while the machine is stationary
giving the charger a considerable degree of centrifugal motion while yet retaining
the charge within it and then by an increase of speed delivering the said charge
over the top of the charger to the revolving cylinder against its sides and above
its bottom flange the cylinder having at that time had its speed sufficiently raised
to spread the sugar wall as described, whereby the said wall inay be quickly spread
by the joint action of centrifugal force and of gravity, substantially as hereinafter
described
In the manufacture of sugar, the saccharine mass to be treated in the centrifugal
machine is taken from the vacuum pan after being crystalized, it then containing a
sufficient amount of syrup to enable the mass to How slowly from the vacuum pan
into a mixer or tank where it is kept agitated while it is being delivered from the
mixer into and worked off from the centrifugal machine
In the usual methods of manufacture the saccharine mass is delivered directly
from the mixer into the cylinder of the centrifugal machine, it having a bottom
and perforated sides, the said bottom sometimes having a central outlet, covered by
a valve for the discharge of the sugar.
In this class of machine the sugar wall has been built by driving the sugar
upward from the bottom of the cylinder toward its top by centrifugal force, but
such method of forming the wall has serious objections because of the limited
height of wall which can be made, for us soon as the cylinder is started the syrup
in the cylinder begins to leave the sugar and before the cylinder has attained a
speed sufficient to overcome the gravitation of the load the sugar becomes sufficiently
dry by the absence of the syrup discharged during the preliminary slow movements
of the cylinder, that by the time the cylinder attains its bigh speed the sugar has
become so dry as to cease to flow and refuses to rise or be drawn up towards and
against the upper flange of the cylinder, and consequently a sugar wall is formed
which not only being thicker at the base than at its top is also irregularly formed,
and results in material waste of sugar during the process of washing.
When the sugar wall is of unequal thickness as described, it also varies very
considerably in color being darker at the bottom. This irregular wall also varies
very considerably in thickness at opposite points of the cylinder, toward the top,
owing to some portion of the charge in the cylinder being slightly more fluid than
other portions.
This unequal deposit of sugar on the walls of the cylinder results very
unfavorably in the operation of the machine because of unequal loading aud
consequent vibration of the machine.
In my study and experiments to overcome difficulties inherent in the present
form of centrifugal machines and to reduce as much as possible the labor required
in the manufacture of sugar, and at the same time increase the capacity of
centrifugal machines and the quality of the work done by them I have devised a
centrifugal machine, the subject of this application, in which the bottom of the
cylinder is lett open as will be described and in which the saccharine mass or charge
as I shall call it to be purged in the cylinder, is first delivered into a charger,
located within the cylinder, and having its upper end below the level of the flange
of the top of the cylinder.
This charger, a solid or impervious pan, having flarring sides has the same
number of revolutions, as the cylinder, and as herein shown is driven by the same
shaft
The charged to be purged is first introduced into the charger at a consistency as
thick as practicable without preventing it from flowing properly-In operation the
charger having been charged, power is applied gently, but the charge is not
delivered into the moving cylinder surrounding the charger until the speed of the
machine is sufficiently rapid to lift the charge in the charger over its top when the
charge is thrown out radially and uniformly in great volume across the space
between the charger and cylinder and against the inner wall of the cylinder which

page_text: wall is perforated as usual and travels at a greater velocity owing to its larger
diameter.
Having retained the sirup in the charge until the machine has reached a speed
sufficiently great to immediately spread the same evenly and perfectly on the
perforated wall of the cylinder, when brought in contact with it, the said charge is
suddenly discharged on the said wall in great volume, and as it spreads, readily
works downward aided by gravitation, so that by commencing the sugar wall at
or near the top of the cylinder and working downward by gravity aided by centri-
fugal action it is practical to make a sugar wall of almost any depth and of
uniform thickness
In this plan with a cylinder of a given size it is practicable with very much less
labor to greatly increase its capacity as compared with other centrifugal machines
and this without increase of power.
In this my improved machine, and by my method the practical size of the
machine is not as heretofore limited-In centrifugal machines heretofore made, the
cylinder has been connected at one end with the spindles, but in this my improved
machine the cylinder is carried by radial arms attached to the spindle the said arms
being connected with the cylinder between its bottom and top, thus allowing free
access to the interior of the cylinder at bottom and top; the over hung portion of
the cylinder more or less counterbalancing the underhung portion, that depending
upon whether or not the connection of the said arms with the cylinder is more or
less central
In practice I prefer nearly a central connection to thus equalize strains and
enable the structure to be built as light as practicable, which is of very great
advantage for high speed.
In connection with the cylinder left open at its bottom I have provided a plow
or scoop which attacks the sugar wall at its base at the bottom of the cylinder the
said plow being introduced into the cylinder from its bottom rather than from its
top as has heretofore been done by me.
The deeper and heavier the sugar wall, the more certain it is to fall by disturbance
at its bottom or base and the cylinder being always open at its bottom the sugar
wall disturbed at its base by the plow will, owing to its great weight fall readily
clear of the machine, thus avoiding the complication of valves which as heretofore
practised had to be opened and closed and had to be kept clean and smooth on
their seats
Figure 1. represents in vertical section a centrifugal machine embodying my
improvements. In the said Figure I show but a portion of its lining in black, and
have omitted over most of the said cylinder the usual perforations made in it (to
thus avoid confusion in the drawing) for in practice the perforations are quite
small.
Figure 2, a horizontal section of Figure 1 on the dotted line xx, a portion of
the charger and cylinder being broken out at one side to show the plow and
sprinkler within it.
Figure 3. is an enlarged detail shewing the connection of the arms with the
cylinder and the method of joining the two sections of the cylinder, and also the
annular gibs for securing the edges of the cylinder lining.
Figure 4 is a section of Figure 3 on the dotted line y-y
Figure 5. is a detail of the lower end of the spindle, and
Figure 6 is a detail showing the method of securing the lining of the cylinder at
the flanges
The spindle a is herein shown as suspended from a spider a² suitably attached
between the two mixers or tanks as a of usual construction secured to the
building
The spindle a is held at its upper end by a nut at and suitable washer, in a
rubber spring a³ and a ball and socket.
The lower end of the spindle a is provided with screw threaded portions aª a³ of

page_text: two different diameters and is reduced to receive upon it the loose bushing a³,
interposed between the spindle and the hub b of the charger 6*.
The hub b is also connected with the hollow shaft b³ which extended upward
has secured to it the driving pulley b' and also the top bushing or bearing for the
spindle a which it will be seen is stationary, while the hollow shaft and charger
revolve about it.
"
The hub of the charger is recessed or chambered as shown in the drawings to
receive a series of loose metal disks or washers 6 upon which the bushing a³ rests,
as the machine travels.
The hub, having been placed on the spindle a as shown in the drawings, and the
said discs 6 having been applied, the nut c is turned upon the screw threaded
portion a of the spindle so that the said nut receives its portion of the weight of
the charger and its connected parts
The nut c having been applied a second bushing c² and series of washers c³ are
applied to the spindle, and the bushing c² is held pressed against its seat, made in
the lower end of the hub by a nut c. The lower end of the spindle with its
attached parts is placed within a chambered foot-piece & suitably shaped and
secured to the said hub b so as to contain oil which latter may stand in the hollow
shaft to its top
The lower end of this foot piece d is extended through a small collar and into
a foot step d³ which latter rests upon a steel block d' set into a piston d¹ fitted into
a cylinder de adapted to be raised or lowered by steam or other fluid introduced
under the said piston through a pipe .
The portion of this piston upon which the foot-step rests and over which it is to
move laterally as the machine centres itself, is drawn to a curve of less radius than
the curve in which the spindle a swings about its ball-joint 2, so that the footstep
as it is moved laterally is obliged to ride up an incline and lift the standing
structure, or else depress the piston d against its initial pressure.
The piston described opposes a definite amount of resistance to the movement of
the foot-step and spindle, and tends to hold the step and spindle at a fixed point
while revolving slowly and the sugar wall is being discharged
In connection with this piston or step and connected with the collar d² are
employed a series of rods e having heads held between springs e² e³. which latter
offer an increased resistance at any attempt of the foot-step to leave the plate d'
or the spindle to move from its axial centre
The charger b is an impervious metal pan having flaring sides and connected at
its bottom with the hub b-The cylinder is preferably made in two sections ƒ ƒ
each provided with a Hange f³ adapted to be bolted together by suitable bolts f*
see dotted lines Figure 3, and the said flanges are separated sufficiently to receive
between them the radial arms g extended through the flaring walls of the charge
and connected with the hub g' or it may be with the hollow shaft b³.
These arms g at their upper ends, are attached to the said hub or shaft by a
tapered key g³ shown in Figure 2 by which the said arms may be lengthened or
shortened separately, and they support the weight of and revolve the cylinder as
often as the charger is revolved.
The entire cylinder shell is in practice perforated as usual and as partially
indicated at 3. Figure 1 and each section of the cylinder has a suitable or usual
perforated lining k shown in Figure 3. and partially in Figure 1, in black but the
perforations in the lining are omitted from the drawing in Figure 1.
4
The cylinder has a top flange ƒ³ and a bottom flange f which define the 5
thickness of the sugar wall.
Each flange near its junction with the body of the cylinder has an annular
groove or recess f7 see Figure 1. to receive one edge of the lining k the said groove
being in practice sufficiently large to receive a flexible washer on hoop k preferably
of wood, see detail Figure 6. by which to retain the said edge in place and 5
protect it
Where the two edges of the cylinder and lining come together or meet I employ

page_text: wedge shaped segmental gibs h³ which are driven into the gap between the adjacent
ends of the two parts of the cylinder sections, the lining being thus bent about the
said ends by the said gibs as shown in Figure 3.
To arrest the movement of the cylinder when desired there are two or more
brakes having pistons or otherwise constructed so as to be operated simultaneously
by steam, air, or other fluid introduced through pipe m having in it a suitable
valve, the said brakes having their faces pressed upward against the underside of
the flange f
If it be desired to wash the sugar wall before the same is broken down, it may
be done by water or other usual liquid discharged through the sprinkler m² herein
shown as attached to a flexible pipe m³, connected with a stand-pipe m*, suitably
supplied with water or other liquid under pressure.
The flexible portion m³ of the pipe will stand in a more or less vertical position
according to the degree of fluid pressure therein; and consequently by varying such
pressure the sprinkler may be made to discharge water or liquid upon different
portions of the sugar wall.
The sugar wall having been formed, and the speed of the machine reduced,
the plown is turned so as to enter the sugar wall above the flange fe as in
Figure 1.
This plow is carried by a piston n³ placed in a cylinder n joined with a pipe n³
suitably connected with a steam or water supply, the said piston, as it moved
upward, causing the plow to travel upon it and gradually act upon the sugar wall.
It is not usually necessary to move the plow u upward, for ordinarily as soon as
the base of the wall is broken the wall above it will fall.
The piston n² has splined to it an arm n³ connected by link n' with an arm of a
rock shaft no having a suitable handle by which to turn it so as to place the plow
in position to act upon the sugar wall, or to remain idle within the central part of
the cylinder. The cylinder is enclosed within the usual curb o³ suitably supported
on brackets connected with the floor.
The plow u has connected with it a wooden scraper p to scrape and clean
the lining of the cylinder for the plow being of metal will preferably not touch
the lining h.
I have shown a second plow ? near the top of the cylinder, the said plow
being carried by a shaft so that it may be turned into or out of working
position
In Figures 1 and 2 it is shown in working position, and it will have a wooden
scraper t to run against and clean the lining h above the arm g-while the sugar
wall is being removed from the machine, the cylinder then being moved at slow
speed the operator may be filling the charger so that the purging process may be
continuous
The saccharine mass as drawn from the gate 3 of the mixer, one or more the
said mass being as thick as practicable and yet flow, is fed into the charger 6 and
suitably charged, the machine is started slowly, and as the speed of the machine
becomes sufficient to overcome the gravity of the load and lift the charger the same
is quickly discharged uniformly in large volume around the entire periphery or the
charger over its top and across the space between it and the interior of the cylinder
against which latter the charge is thrown near its top the sugar quickly spreading
and descending under the combined action of centrifugal force and gravity, the
sirup passing through the lining and cylinder wall, leaving the sugar in the
condition of a vertical wall of uniform thickness and of auy desired depth, for the
depth of the wall is not by this plan limited as in centrifugal machines where
the sugar wall is thrown up from the cylinder against its own gravitation by
centrifugal action.
The wall so formed may be washed if considered necessary and thereafter the
plow will be put into position to attack the base of the sugar wall, and demolish
it, when the portion of the sugar wall above it will drop by gravity and fall freely

page_text: through the open bottom of the cylinder, there being nothing at the bottom of the
cylinder to impede the fall of the sugar.
I have described my apparatus as operating upon sugar but I do not intend to
limit my invention for use with sugar only, as my improved mechanical organisation
and method may be employed with good results in connection with any substances
commonly treated by centrifugal machines.
As so far described I have omitted all reference to the extended flange of the
charger, as in some instances I shall omit the same altogether therefrom.
In some classes of work however the flange aids in causing the delivery of the
charge into the space limited at botton and top by the flanges of the cylinder; and
prevents the dropping of the material from the charger through the centre of the
machine within the circle bounded by the lower flange.
Having described my invention I claim as follows
In a centrifugal machine the combination with the revolving cylinder with an
impervious pan-like charger located within it to receive the sirupy mass or charge
hold it, and when the machine is in motion discharge the charge outwardly against
the wall of the cylinder substantially as described.
Also the rotating shaft, and connected centrally impervious pan-like charger
combined with an outer perforated cylinder and with arms to unite the charger
with the cylinder between its ends as described, so as to rotate the cylinder in
unison with the charger as and for the purpose set forth
Also in a centrifugal machine the cylinder having its lower end open or
unobstructed at its centre, combined with a plow adapted to be entered into the
sugar wall and with means to operate the said plow through the bottom of the said
cylinder substantially as described
Also the improvement in the art or method of purging sugar which consists in
supplying the material or charge into an impervious charger while at rest and
occupying a central position with relation to the cylinder and discharging the
same in volume from the charger into the cylinder over the top of the charger
after the same has had its speed raised sufficiently to force the charge outwardly
therefrom, thereby immediately spreading the charge to form a wall substantially
as described.
Also that improvement in the art or method of purging sugar which consists in
supplying the charger of the machine with a charge while the machine is stationary
giving the charger a considerable degree of centrifugal motion while yet retaining
the charge within it and then by an increase of speed delivering the said charge
over the top of the charger to the revolving cylinder against its sides and above
its bottom flange, the cylinder having at that time had its speed sufficiently raised
to spread the sugar wall as described whereby the said wall may be quickly spread
by the joint action of centrifugal force and of gravity substantially as described.
In witness whereof I the said Alfred George Brookes have hereunto set my
hand and seal this seventeenth day of April in the year of our Lord One thousand
eight hundred and eighty three.
ALFRED & BROOKES. (L.S.)