An Improved Continuously Operating Centrifugal Machine.
Year: 1892

page_text: Date of Application, 16th May, 1892-Accepted, 18th June, 1892
COMPLETE SPECIFICATION.
An Improved Continuously Operating Centrifugal Machine.
We, IGNAZ VON SZCZENIOWSKI and GUSTAV VON PIONTKOWSKI, in the
Kapusciany Sugar Factory, Podolien, in the Russian Empire, 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 that class of centrifugal machines in which the material
under treatment is driven upwards by centrifugal force from the bottom of a sieve
or drum which tapers outwardly to the inner walls of the latter.
The object of this invention is a centrifugal machine in which a perforated sieve
like drum is adjustable vertically, its upper edge being somewhat bent inwardly and
surrounded by a short cylindrical sieve which only takes part in the rotary motion
of the drum when the latter is raised or lowered but remains otherwise stationary,
so as to retard or accelerate the discharge of the material according to the
adjustment of the drum relatively to the cylindrical sieve.
The invention refers moreover to mechanism adapted to this centrifugal machine
for the purpose of regulating the thickness of the layer of material driven upwards
against the inner walls of the drum; of ensuring the uniform distribution of the
covering liquid, whether steam, water, or cleare (fine liquor produced in the manu-
facture of sugar) upon the material under treatment; of allowing the covering
liquid to remain long enough in contact with the material, and finally of catching
up and feeding forward the material passing over the upper edge of the said
cylindrical sieve.
The accompanying drawings illustrate a centrifugal machine provided with the
improved mechanism above mentioned.
Figure 1 is a side view thereof. Figure 2 a central vertical section, and Figure 3
a plan partly in section of the same.
a, Figure 2 is the conical drum tapering upwardly and the upper part or edge of
which is somewhat bent inwardly. This drum is firmly fixed upon the vertical main
shaft B carrying the driving pulley D and resting below upon a step bearing C
which can be raised or lowered by means of the adjustable device F.
When this
device has to be raised or lowered, the drum is correspondingly lifted or sunk,
whereby the distance between its upper edge and the upper edge of a cylindrical
rim 6 can be decreased or increased respectively, this rim surrounding the upper
and inwardly bent edge of the drum, so as to adhere tightly thereto. This rim b
which is formed like a cylindrical sieve is carried with the aid of the arms m, which
are arranged around the drum and extend obliquely upwards, by the hollow shaft E
through which the main shaft B passes. The hollow shaft turns in a collar or
bearing n in which it can move freely while being incapable of shifting in an
upward direction; between the front walls of this bearing and the discs fixed above
and below on the hollow shaft E are placed a number of balls for the purpose of
reducing the friction when the hollow shaft rotates.
The mechanism consisting of the hollow shaft E of the arms m connected
together centrally by the ring m¹ and of the rim 6 rotates with the main shaft B
and the drum a, the latter being provided upon its outer periphery with a number
of forked brackets u, each of which embraces one of the arms carrying the rim b.
The consequence of this arrangement is that the cylindrical sieve or rim 6 partakes
only of the rotary motion of the drum a but not of its up and down shifting motion
caused by the adjustment of the step bearing C. According to the nature of the
material to be treated the position of the drum a is raised or lowered relatively to
the rim b; but for the same material the adjustment effected is maintained
throughout.

page_text: The material required to be treated is fed by a travelling screw G at the top,
Figure 2, to the funnel H and falls from this funnel upon the solid bottom of the
perforated drum a which is covered outside with a sieve or wire gauze, whence
the said material is dashed by centrifugal power through the side slots of a ring or
collar P, projecting upward from the bottom of the drum against the side walls of
the said drum, being subsequently fed upwards along the same.
To ensure that only a layer of material of uniform thickness should be fed
upwards along the central and upper part of the inner walls of the drum a, the
perforated flanged disc c is provided and screwed upon the collar P at the bottom
of the drum being arranged and adjusted in such a manner that between its outer
edge and the inner wall of the drum a a circular opening or passage d of the desired
width is formed.
As the material lingers in that part of the drum which is below the disc c it is
freed from the greatest part of the liquid contained therein which passes through
the walls of the drum and falls on the bottom of the casing A of the centrifugal
machine, being discharged outside through the outlet . The material thus freed
from water is treated according to requirements with a liquid or gaseous covering
after having first passed through the opening d formed, as above stated, between
the disc cand the inner wall of the drum and having been subsequently fed
upwards. This covering is introduced through the pipe J above the disc c and is
uniformly distributed by the oblique blades or fly e (Figure 3) which is fixed
on the upper part of the disc c between the latter and a ring f arranged
higher up. The disc c, the fly e, and the ring f form one piece which partakes
of the rotary motion of the drum a, owing to the disc being mounted on the
fixed collar secured to the bottom of the drum. As soon as the material has
passed on its way up beyond the outer edge of the ring f, the inner part thereof
arrives below a bag of conical form and made of any suitable fabric, tissue, leather,
india rubber and the like, this bag being fixed below to the ring f and turning with
the drum a while stretching freely upwards. This bag is tightly held by centri-
fugal power against the drum a and the upper part of the rim 6, and has for its
object to retain, for a sufficient period of time, the liquid or steam cover upon the
material so as to promote its action thereon. The liquid expelled from the upper
part of the drum falls in a circular canal to which is formed upon the inner wall of
the casing A and is provided with an outlet g. The steam likewise issuing from the
upper part of the drum a is removed by a ventilator or fan consisting of the fly
fixed to the carrier arms of the rim and moving in a sheet iron frame resting upon
the casing A and furnished with an outlet opening (see also Figure 3).
The material now separated from the liquid reaches as it leaves the upper edge
of the drum a, the inner walls of the likewise perforated rim b which is covered
with a sieve and upon which the centrifugal force acts radially so that the material
can no more be propelled upwards by the centrifugal force. The material collects
subsequently upon the inner walls of the cylindrical sieve band forms a circular
layer, remaining at rest in consequence of the friction which it exerts upon the
said sieve 6 until the pressure of the material following on underneath has become
great enough to overcome this friction. The material on the cylindrical sieve takes
now an ascending course and is pushed by the material underneath over the upper
edge of the said sieve whence it is removed outside.
The higher the rim projects above the upper edge of the drum a the greater is
the mass of material which is collected on the said rim or sieve and the greater is
also the resistance which the material accumulating likewise upon the walls of the
drum a and following underneath has to overcome in order to feed upward the
material collected on the sieve or rim b.
By suitably adjusting the drum relatively to the sieve the length of time during
which the material is to remain under treatment in the centrifugal machine can be
accurately regulated.
The material passing over the upper edge of the rim b is expelled in a tangential
direction. against the side walls of a hood i furnished with a number of curved
5

page_text: scoops k, Figures 2 and 3; these scoops catching the material and allowing it to
fall in a circular groove or channel. The rotary motion imparted to the hood i,
by means of the screw and worm wheel r¹, and which takes place in a contrary
direction to that of the drum enables the scoops k to propel the material in the
channel over the openings y formed in the bottom of the said channel whence the
said material is removed outside.
When the above described centrifugal machine is used for operating on a sugar
mass, it requires only to be rotated at a speed of 410 revolutions per minute with a
diameter of 1500 m, wherefor one horse power is sufficient, the machine will then
produce 3600 kgs. of raw sugar, or 2000 kgs. of pure dried sugar of commerce, and
1000 kgs. of bye-products.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
:-
1. A continuously operating centrifugal machine in which the upper part of the
conical drum a which tapers upward is somewhat bent inwardly and is surrounded
by a perforated rim 6 turning therewith and arranged in such a manner that the
drum can be raised or lowered relatively to the rim according to the nature of the
material under treatment or to the kind of product it is required to obtain,
the rim being fixed to the drum when the same sort of material is constantly being
treated.
2. In the machine above claimed, the arrangement of a horizontal disc c
inside the drum, in such a manner that between the outer edge of the disc and
the inner wall of the drum a circular opening is formed the width of which can
be altered by a corresponding adjustment of the disc for the purpose of regulating
the thickness of the layer of material driven upwards along the inner walls of
the drum.
3. In the machine claimed above, the arrangement for the purpose of uniformly
distributing the covering used (steam, water, cleare, and the like) of a fly e on the
disc mentioned in Claim 2, this fly being placed obliquely and connected at the top
with a ring f.
4. In the machine above claimed, the arrangement of a conical bag h formed of
any suitable fabric, leather, india rubber, or other material, this bag being placed
above the covering fluid distributing mechanism above claimed, in such a manner
as to be tightly pressed by centrifugal force against the drum a and the rim & for
the purpose of bringing the steam or other covering fluid into a sufficiently prolonged
contact with the material under treatment and of preventing the material from
drying inside the drum.
5. In the machine above claimed, a receptacle surrounding the said machine at
the top and serving to catch and collect the finished product expelled from the
rim b, consisting of the circular channel o and the hood i arranged over the same
and provided at its inner walls with a number of curved scoops k, this hood i being
either fixed, or capable of rotating, and feeding in the latter case by means of its
scoops the product collected in the said channel o over the openings formed in the
said channel.
6. In the machine above claimed, the use of a ventilator or fan for the purpose
of removing the steam and vapours, this fan or ventilator being formed by the fly e
fixed to the drum a, i.e. to the carrier arms of the rim b, provided with a suitable
outlet and moving in a suitable frame or casing.
ULLIS IUGUY IN INELY LO9Z
TUAIS IUGI UHLY NHLY LONZ
H. GARDNER,
Per R. Core Gardner,
Patent Agent, 166, Fleet Street, London,
Agent for the said Ignaz von Szczeniowski and Gustav von Piontkowski.