Improvements in Centrifugal Apparatus for Drying and Purifying Sugar or other Crystalline or Granular Matters.
Year: 1894

page_text: Date of Application, 27th Jan., 1594
Complete Specification Left, 25th Oct., 1894-Accepted, 1st Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Centrifugal Apparatus for Drying and Purifying
Sugar or other Crystalline or Granular Matters.
I, DUNCAN STEWART, of The London Road Iron Works, in the County of the
City of Glasgow, North Britain, Engineer, do hereby declare the nature of this
invention to be as follows, that is to say :-
my
My said invention relates to centrifugal apparatus of the kind described in
Patent Specification No. 13655 of 1888 and has for its object to construct such
apparatus in an improved manner, and so that it may operate continuously and
satisfactorily for drying and purifying sugar or other crystalline or granular
matters.
In carrying out my invention I place the turbine or rotating basket with its axis
horizontal, and arrange within it a hollow drum fixed on a central shaft, and leaving
an annular space between its outer surface and the inner surface of the turbine.
The turbine and inner drum are made taper or slightly conical in form, and the
moist sugar or other crystalline or granular matter is introduced between them
at the smaller end. To insure the proper distribution of the sugar or other matter
when being introduced, it is fed from a hopper into a kind of gland which
encircles a cone fixed to the smaller end of the turbine, this cone being made
with an elongated tubular centre or boss which bears on the central horizontal
shaft. The feeding-in gland is at the outer and smaller end of the cone; and
the cone is made with an outer conical shell between which and the body of the
cone there is an annular conical space the smaller part of which communicates with
the feeding-in gland whilst the larger part communicates through apertures with the
space between the turbine and inner drum. The sugar or matter entering at the
smaller part of the cone is by the centrifugal action due to the rotation spread over
the cone and carried into the space between the turbine and inner drum.
The inner drum is fixed on the central shaft by means of arms, and it is made
with holes to allow air free access from its interior into the annular space. On the
outside of the inner drum helical blades are fixed for controlling the movement of
the sugar or other matter from the smaller to the larger end of the turbine, there
being a suitable difference between the speeds of the turbine and inner drum to
The helical blades are made of a
effect the proper action of the belical blades.
larger pitch at the larger part of the turbine so that the sugar or other matter may
move more quickly along at that part. The turbine is, by means of a disk at its
larger end, fixed on a tubular shaft through which the central shaft extends. The
shafts are supported in the necessary bearings and each has on it a separate pulley
for a driving belt. One of these pulleys may be made variable in effective diameter
in order that the relative speeds of the turbine and inner drum may be adjusted so
as to get the best action of the helical blades. For this purpose the pulley is made
with the rim in segments, each segment being formed with a sector which has
formed or fixed on it teeth or studs engaging between spiral teeth or in spiral
grooves formed on a disk fixed on the shaft. When the segments are adjusted with
a turning movement relatively to the disk, they are shifted out or in through the
action of the spiral grooves or teeth.
The turbine, made by preference of cast brass, is shaped and turned with all
possible accuracy, and it is encircled by flanges which are bound by steel rings, the
end flanges projecting in such manner as to prevent escape of liquid through the
end openings in the casing which encloses the turbine and receives the liquid
thrown through the walls of the turbine by the centrifugal action. The sugar or

page_text: other matter dried by the centrifugal action is delivered at the larger end of the
turbine through circumferential openings into a separate compartment or casing
provided to receive it.
Provision is made for causing a spray of water with or without steam or of
any suitable liquid to act internally on the sugar or other matter whilst in the
turbine for the purpose of cleansing or purifying it. And provision is also made
for directing sprays or jets of water or other fluid upon the outside of the
turbine for the purpose of keeping the perforations through the sides of the turbine
clear.
For the internal spray action, the central shaft is made tubular and water or
other fluid is introduced through the tubular part of the shaft whence it is led by
branch pipes to pipes which extend along the inside of the inner drum and are
perforated on their outer sides.
For the external sprays or jets, sets of longitudinal pipes are arranged at a
suitable distance from the turbine and are perforated so as to direct spray or jets
upon the turbine. In each set there are six or other suitable number of the
perforated pipes arranged equi-distantly around the turbine, and each set is supplied
by a different branch pipe having on it a regulating valve. One set of the spray
pipes operates on the smallest part of the turbine, another set or sets on intermediate
parts, and a set on the largest part, and the treatment of each part can be
separately modified as may be found desirable in practice.
Circular
The turbine shell is by preference perforated in the following manner.
recesses are formed in the outer side of the shell and then perforations of suitable
small size are made through the thinner metal of the recesses, the thicker metal
between the recesses giving ample strength to the whole.
Dated this Twenty-sixth day of January 1894.
EDMUND HUNT,
Applicant's Agent.
COMPLETE SPECIFICATION.
Improvements in Centrifugal Apparatus for Drying and Purifying
Sugar or other Crystalline or Granular Matters.
I, DUNCAN STEWART, of The London Road Iron Works, in the County of the
City of Glasgow, North Britain, 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, that is to say :-
My said invention relates to centrifugal apparatus of the kind described in my
Patent Specification No. 13,655 of 1888; and has for its object to construct such
apparatus in an improved manner, and so that it may operate continuously and
satisfactorily for drying and purifying sugar or other crystalline or granular
matters.
Centrifugal apparatus, as made with my improvements, is shown on two
accompanying sheets of explanatory drawings, Figure, 1, on Sheet, 1, being a
longitudinal vertical section, Figure, 2, on Sheet, 2, being an elevation as at right
angles to Figure, 1, and Figures, 3, and, 4, being respectively an elevation and a
section, as at right angles to each other, of details hereinafter described. In these
drawings the same reference letters and numerals are used to mark the same or like
parts wherever they are repeated.
In carrying out my invention I place the turbine or rotating basket, A, with its
axis horizontal, and arrange within it a hollow drum, B, fixed on a central shaft, C,
and leaving an annular space between its outer surface and the inner surface of the
turbine, A. The turbine, A, and inner drum, B, are made taper or
slightly conical
in form, and the moist sugar or other crystalline or granular matter is introduced
between them at the smaller end. To insure the proper distribution of the sugar

page_text: or other matter when being introduced, it is fed from a stationary hopper, D, into a
kind of gland, D 1, which encircles a cone, A 1, fixed to the smaller end of the
turbine, A, this cone being made with an elongated tubular centre or boss, A 2,
which bears on the central horizontal shaft, C. The feeding-in gland, D 1, is at the
outer and smaller end of the cone, A 1; and the cone has fixed to it an outer conical
shell, A 3. Between the shell, A 3, and a conical part of the hopper gland, D 1,
and the body of the cone, A 1, there is an annular conical space the smaller part of
which communicates with the feeding hopper, D, whilst the larger part
communicates through apertures with the space between the turbine, A, and inner
drum B. The sugar or matter entering at the smaller part of the cone, A 1, is by
the centrifugal action due to the rotation spread over the cone and carried into the
space between the turbine, A, and inner drum, B.
The inner drum, B, is fixed on the central shaft, C, by means of arms, B 1, and
it is made with holes (not shown) to allow air free access from its interior into the
annular space. On the outside of the inner drum, B, helical blades, B 2, are fixed
for controlling the movement of the sugar or other matter from the smaller to the
larger end of the turbine, A, there being a suitable difference between the speeds of
the turbine and inner drum to effect the proper action of the helical blades. The
helical blades, B 2, are made of a large pitch at the larger part of the turbine, A,
so that the sugar or other matter may move more quickly along at that part. The
turbine, A, is by means of a disk, F, at its larger end fixed on a tubular shaft, G,
through which the central shaft, C, extends. The shafts, C, and, G, are supported
in the necessary bearings, H 1, H 2, and H 3, and each has on it a separate
pulley, J, K, for a driving belt. The pulley, J, on the central shaft, C, is made
smaller so that the speed of the inner drum, B, may be less than the speed of the
turbine, A, to allow of the action of the helical blades, B 2, herein before
mentioned.
The turbine, A, made by preference of cast brass, is shaped and turned with all
possible accuracy, and it is encircled by flanges, A 4, which are bound by steel
rings, A. 5, the end flanges projecting in such manner as to prevent escape of liquid
through the end openings in the casing, L, which encloses the turbine and receives
the liquid thrown through the walls of the turbine by the centrifugal action. The
sugar or other matter dried by the centrifugal action is delivered at the larger end
of the turbine, A, through circumferential openings, M, into a separate compartment
or casing, N, provided to receive it.
Provision is made for causing a spray of water with or without steam or of any
suitable liquid to act internally on the sugar or other matter whilst in the turbine, A,
for the purpose of cleansing or purifying it. And provision is also made for
directing sprays or jets of water or other fluid upon the outside of the turbine, A,
for the purpose of keeping the perforations, P, (Figures, 3, and, 4) through the
sides of the turbine clear.
For the internal spray action the central shaft, C, is made tubular and water or
other fluid is introduced through the tubular part of the shaft, whence it is led by
branch pipes, Q, to pipes, Q 1, which extend along the inside of the inner drum, B,
and are perforated on their outer sides.
For the external sprays or jets sets of longitudinal pipes, R, are arranged at a
suitable distance from the turbine, A, and are perforated so as to direct spray or
jets upon the turbine. In each set there are six or other suitable number of the
perforated pipes, R, arranged equi-distantly around the turbine, A, and each set is
supplied by different branch pipes, S, having on them if desired separate regulating
valves (not shown). One set of the spray pipes, R, operates on the smallest part of
the turbine, A, another set or sets on intermediate parts and a set on the largest
part, and the treatment of each part can be separately modified as may be found
desirable in practice.
The turbine shell, A, is by preference perforated in the following manner.
Circular recesses, T, (Figures, 3, and, 4,) are formed in the outer side of the
shell, A, and theu perforations, P, of suitable small size are made through the

page_text: thinner metal of the recesses, the thicker metal between the recesses giving ample
strength to the whole.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. The constructing, combining, and arranging of the parts constituting as a
whole the improved centrifugal apparatus for continuously drying and purifying
sugar or other crystalline or granular matters substantially in the manner herein-
before described and as shown in the accompanying drawings.
2. In centrifugal apparatus of the kind to which the invention relates, providing
means to apply regulated sprays or jets of water or steam or other fluid to the
inside of the inner perforated drum substantially as and for the purposes hereinbefore
described.
3. In centrifugal apparatus of the kind to which the invention relates providing
means to apply regulated sprays or jets of water or other fluid to the outside
of the outer turbine or basket substantially as and for the purposes hereinbefore
described.
4. In centrifugal apparatus of the kind to which the invention relates forming
the outer turbine or basket shell with circular recesses the bottoms of which are
perforated substantially as hereinbefore described and as shown in Figures, 3, and, 4,
of the accompanying drawings.
Dated this Twenty-fourth day of October 1894.
EDMUND HUNT,
Applicant's Agent.