Improvements in Centrifugal Liquid Separators.
Year: 1893

page_text: Date of Application. 21st Aug., 1893-Accepted, 11th N v., 1593
COMPLETE SPECIFICATION.
Improvements in Centrifugal Liquid Separators.
We, CARL JOHAN LUNDSTRÖM, Mechanical Engineer, DAVID HAMLIM
BURRELL, and EDWARD JONATHAN BURRELL, Manufacturers, all of Little
Falls, in the County of Herkimer, and State of New York, United States of
America, 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 separating machines which
are employed for separating a compound liquid or emulsion into its constituent
liquids of different densities, particularly for separating full milk into cream and
skim milk.
One object of this invention is to provide the bowl of the separator with a
simple device for increasing its separating capacity.
Another object of this invention is to provide simple means for intercepting
the solid impurities contained in the milk before they reach the outer wall of
the bowl.
A further object of this invention is to connect the spindle and the bowl in
such manner that the bowl is compelled to rotate with the spindle but permitted
to balance itself on the spindle within certain limits.
A still further object of this invention is to improve the step bearing on which
the spindle turns, so as to reduce the friction by a simple, durable and inexpensive
device.
In the accompanying drawing
Figure 1 is a sectional elevation of a centrifugal cream separator provided with
these improvements.
Figure 2 is a sectional elevation of the step bearing, on an enlarged scale.
Figure 3 is a horizontal section through the step bearing on the line 3—3,
Figure 2.
Figure 4 is a sectional elevation of the yielding driving device interposed
between the spindle and the lower portion of the bowl.
Figure 5 is a vertical section of the joint between the cover and the body of the
bowl, on an enlarged scale.
Figure 6 is a sectional elevation of the bowl and connecting parts on an enlarged
scale.
Figure 7 is a horizontal section on the line 7-7, Figure 6.
Like letters of reference refer to like parts in the several figures.
A represents the stationary curb or casing supported on the frame A' in the
usual way.
B is the separating bowl or drum, and b the driving spindle thereof.
The upper part of the spindle is journaled in a bearing a which is arranged in the
upper part of the frame A' and made laterally yielding by a rubber ring a' inter-
posed between the bearing and the surrounding portion of the frame in the usual
manner. The spindle extends upwardly above the upper bearing a and into the
This hub rests
hollow conical hub B¹ formed on the bottom B2 of the bowl.
loosely upon the rounded upper end of the spindle so that the bowl is capable of a
limited rocking movement on the spindle. This oscillatory movement is limited by
a yielding connection which is interposed between the lower portion of the hub and
the spindle and which is constructed as follows
C is a sleeve which surrounds the spindle within the lower portion of the conical
hub. This sleeve is provided in its lower edge with a notch c by which it is
interlocked with a pin c' secured to the spindle, so that the sleeve is compelled to
turn with the spindle. Other suitable devices may however be employed for this
ruo21

page_text: purpose. d is a yielding ring, preferably of rubber, which surrounds the sleeve and
is seated in an annular groove formed in the outer surface of the sleeve. D is a
flanged collar which surrounds this yielding ring and which is secured to the
bottom of the bowl. This collar is provided on its inner surface with an annular
groove in which the yielding ring is also seated, so that the ring is clamped
between the sleeve and the collar. This yielding nature of the ring permits of a
slight oscillation of the bowl on the spindle in balancing itself and the frictional
contact of the yielding ring with the sleeve and collar transmits the motion of the
spindle to the bowl and causes the latter to rotate with the spindle.
E represents the cover of the bowl which is contracted upwardly to a neck e in
which the cream discharge pipe e¹ is arranged and through which the skim milk
pipes e² open. F is the skim milk receptacle resting upon the curb A and F' is the
cream receptacle resting upon the skim milk receptacle F, both of ordinary con-
struction. The cover E is provided at its lower end with an external screw
thread g by which it is screwed into a flange g¹ formed on the upper end of the
peripheral wall of the bowl and provided with an external screw thread and with a
seat for the packing ring h. This cover is provided on the inner side of the
packing ring with a depending lip which confines the packing ring and which
may be arranged flush with the inner surface of the peripheral wall of the bowl,
as shown in Figure 6, or which may overhang the inner surface thereof, as shown
in Figure 5.
I represents the stationary feed cup resting upon the cream receptacle F and
provided with a feed pipe i which extends downwardly into the bowl. J represents
the rotating feed cup secured to the apex of the hub B¹ of the bowl and provided
with one or more discharge pipes ; which extend outwardly into the bowl beyond
the cream wall.
K represents a hollow separating cone which is arranged in the liquid space of
the bowl and which rests upon the bottom of the bowl at or near the peripheral
wall thereof and extends upwardly and inwardly from the bottom toward the cream
outlet and terminates with its contracted end in the vicinity of the cream outlet.
This cone extends diagonally through the thickness of the annular body of liquid
in the bowl and divides that body into an inner portion, which is located inside of
the cone, and an outer portion which is located between the cone and the
peripheral wall of the drum. The diameter of the small end of the cone is such
that the cream, which is separated on the inner side of the cone, can pass upwardly
beyond the small end of the cone and reach the cream outlet of the bowl. The
diameter of the small end of the cone is preferably about the same as that of the
circle formed by the cream wall where it escapes from the neck of the bowl. The
smaller the diaineter of the small end of the ccne the thicker, is the cream which is
discharged therefrom.
L represents upright blades which are secured to the outer surface of the cone
and which extend to the peripheral wall of the bowl, or nearly to the same.
These
blades prevent the liquid on the outer side of the cone from changing its position
circumferentially within the bowl and they also divide the liquid space between the
bowl and the cone into several upright spaces in which the liquid is comparatively
quiet, whereby the separation of the cream from the skim milk in the outer liquid
space is promoted.
m represents openings formed in the cone at a short distance above the lower end
and establishing communication between the inner liquid space and the outer liquid
space above the lower edge of the bowl. These openings permit of the free passing
of liquid from the inner to the outer side of the cone, when the lower edge of the
cone has become encumbered with deposited solid matter, and so permit of the
interception of the solid impurities contained in the milk on the inner side of
the cone, along the lower edge thereof, without interfering with the flow of the
liquid from the inner to the outer side of the cone, while the cone prevents the
solid impurities from being deposited against the outer wall of the bowl.
The full milk escaping from the discharge pipes of the feed cup enters first

page_text: the liquid space on the inner side of the cone and is there subjected to centrifugal
action whereby the cream globules are crowded toward the axis of rotation while
the globules of skim milk are driven outwardly. The cream globules accumulate
in the inner layer of the inner body of liquid and move gradually upwardly toward
the small end of the cone and past the same to the cream outlet of the bowl. The
particles of skim milk reach, in their outward course, the inner surface of the cone
and travel downwardly along the latter under the influence of centrifugal force and
finally escape through the openings m and around the lower edge of the cone into
the outer liquid space. In this space the partially skimmed milk is further
separated, the cream globules being crowded inwardly against the outer side of the
cone, while the particles of blue or skim milk accumulate on the inner side of the
peripheral wall of the bowl and flow upwardly along the same to the outer ends of
the skim milk pipes. The cream separated on the outer side of the cone unites
above the small end of the cone with that which is separated on the inner side of
the cone.
The full milk is by this means subjected to a primary separation on the
inner side of the cone, whereby the largest cream globules, which have the greatest
buoyancy and are most readily separated, are first separated from the milk, and
the partially skimmed milk, which accumulates. in the outer layer of the inuer
portion of the body of liquid, is then subjected on the outer side of the cone to a
further or secondary separation, whereby the smaller cream globules having less
buoyancy, are separated from the skimmed milk and whereby the operation of
skimming is completed.
This separating cone is very simple and inexpensive and it adds but little to the
weight of the bowl, so that the machine can be operated with the same power
required for operating the bowl without the cone, while the separating capacity is
largely increased. The cone can be readily removed when required to be cleaned.
By providing several cones of different diameters at the small end, the consistency
of the cream which is delivered by the machines can be changed by changing
the cone.
n represents the lower reduced portion of the spindle, N the bearing which
surrounds the same and extends below it, and O the step inserted in the lower end
of the bearing. p is a steel ball arranged in the bearing upon the step and below
the spindle. This ball is somewhat smaller in diameter than the diameter of the
spindle so that the point at which the spindle rests upon the hall lies outside of the
centre line of the spindle, whereby the ball is compelled to travel in a circular path
with the spindle. The ball is arranged in the open chamber formed in the bearing
below the spindle and free to change its position and it has its bearing points at the
top, bottom and outer side, whereby the ball wears uniformly, while the friction is
greatly reduced.
While this machine has been described as applied to the creaming of milk it may
be used for the separation of other compound liquids.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The combination with the separating bowl having an inlet for the full milk
and discharges for the separated cream and skim milk, of a hollow separating cone
extending diagonally through the liquid space of the bowl from the bottom of the
bowl toward the cream outlet and terminating with its small end near the cream
outlet.
2. The combination with the separating bowl having an inlet for the full milk
and having its cover provided with a contracted neck in which the outlets for the
cream and skim milk are arranged, of a hollow separating cone resting with its base
upon the bottom of the bowl and terminating with its small end near the contracted
neck of the bowl.
3. The combination with the separating bowl having an inlet for the full milk
and discharges for the separated cream and skim milk, of a hollow separating cone

page_text: extending diagonally through the liquid space of the bowl from the bottom of the
bowl towards the cream outlet and terminating with its small end near the cream
outlet, and wings or blades secured to or formed on the outer surface of such cone
and extending through the liquid space between the cone and the bowl.
4. The combination with the separating bowl having an inlet for the full milk
and discharges for the separated cream and skim milk, of a hollow separating cone
extending diagonally through the liquid space of the bowl and provided near its
large end with openings through which the liquid passes outwardly.
5. The combination with the spindle and the separating bowl having a hub
extending from its bottom and hung loosely upon the spindle, of a sleeve surrounding
the spindle within the lower portion of the hub, and a yielding ring interposed
between said sleeve and the bowl.
6. The combination with the spindle, of the step bearing extending below its
lower end, a step secured in said bearing, and an anti-friction ball of less diameter
than the spindle arranged loosely in the chamber between the spindle and
the step.
Dated this Olst day of August 1893
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.