Year: 1888

page_text: Date of Application, 17th Dec., 1888
Complete Specification Left, 30th Apr., 1889-Accepted,-8th June, 1889
We, JOHN LAIDLAW and JAMES WRIGHT MACFARLANE both of 98 Dundas Street,
Kingston, Glasgow, in the County of Lanark, North Britain, Engineers do hereby
declare the nature of this invention to be as follows :-
This Invention, which relates to improvements in centrifugal machines for separating
cream from milk, has for its object generally to render such machines more efficient
than hitherto and to simplify the construction thereof.
The first part of the improvements have reference to the construction of the
separating drum. This drum is composed of an upper conical part having the smallest
end of the cone uppermost. At its lower end the cone is screwed into or otherwise
suitably attached to the lower part of the drum which consists of a ring having an
inclined face at its bottom leading by a curved surface to the discharge lip and which
constitutes the skim-milk collecting and discharge chamber. To the spindle which
carries the separating drum a circular diaphragm is attached and this diaphragm is
held at its periphery firmly between the upper and lower parts of the separating drum.
Upon the upper part of the boss by which the diaphragm is carried upon the spindle
a milk-receiving-cup rests. This cup is approximately hemispherical or conical in its
internal contour and at its upper part it carries an internally projecting flange which
is of such an external diameter as to completely close or fill the mouth of the drum.
The milk is fed into this cup by a regulator. At suitable intervals round the upper
part of the periphery of this cup a series of small holes are formed through which the
milk by centrifugal action passes into the separating drum. The object of the internal
flange hereinbefore referred to is to permit of a sufficient head or pressure of milk
being always maintained by centrifugal action against these holes and so causing solid
streams of milk to continually be forced through these holes thereby preventing
passage of air therethrough.
It is here explained that the rate of feeding is such and the size of the holes is such
as to ensure this end being accomplished.

page_text: The milk on passing through the aforesaid holes in the receiving-cup passes down
the conical interior of the upper part of the separating drum until it reaches the bottom
thereof at which point the separated-milk passes through a series of holes at or near
the periphery of the diaphragm into the skim-milk collecting chamber. Simultaneously
with the passing out of the skim milk the separated cream floats towards the bottom
of one or more discharge guides each of which consists of a vertical or slightly
inclined channel formed on the inner edge of each of the vanes which are fixed inside
the separating drum. Near the upper part of each of these channels a discharge
orifice is situated through which the cream passes by centrifugal action into the
annular collector which surrounds the machine and from which it is drawn off. Each
of the channels herein before referred to is formed to project inwards at the top so as
to cause a solid body of cream to collect over the discharge orifices each of which are
made small enough to prevent air passing through with the cream.
The holes in the diaphragm through which the skim-milk passes are made as
numerous as possible in order to prevent the edifying action which would take place if
only a few holes were used therein.
The lip over which the skim-milk escapes may be varied in diameter so as to
regulate the rate and degree of separation and fixed vanes may be used in the skim-
milk chamber such as these herein before described as being used in the upper chamber
but without channels or guides. To the underside of the lower part of the drum and
at a distance exterior to the discharge lip thereof an annular collecting chamber may
be formed into which the skim-milk passes by centrifugal action. From this the milk
is removed by a bent elevating pipe or its equivalent as is well understood.
When it is not desired to remove the milk from the annular collecting chamber by
a pipe as aforesaid the skim milk overflows from this chamber by centrifugal action
into a fixed annular collector like that hereinbefore described for collecting the
cream.
The aforesaid separating drum is so attached to its spindle as to be easily removed
therefrom for being washed or cleansed.
The improvements consist in the second place in the construction of the footstep
bearings for centrifugal machines. The lower part of the spindle is either made
conical or flat and it rests upon a hard steel sphere which again rests upon a flat steel
plate.
"
ST. JOHN V. DAY,
115, St. Vincent Street, Glasgow,
Petitioners' Agent.

page_text: We, JOHN LAIDLaw, and James WRIGHT MACFARLANE, both of 98 Dundas Street,
Kingston, Glasgow, in the Counties of Lanark and Renfrew, North Britain, Engineers
do hereby declare the nature of this invention and in what manner the same is to
be perforined, to be particularly described and ascertained in and by the following
statement :-
Our Invention which relates to improvements in centrifugal machines for separating
cream from milk and other more or less analogous substances, has for its object
generally to render such machines more efficient than hitherto, and to simplify the
construction thereof.
The first part of the improvements has reference to the construction of the separating
drum. This drum is composed of an upper conical part, having the smallest end of
the cono uppermost. At its lower end, the cone is screwed into, or otherwise suitably
attached to the lower part of the drum which consists of a ring having an inclined
face at its bottom leading to the discharge lip, and which constitutes the skim-milk
collecting and discharge chamber. To the spindle which carries the separating drum
a circular diaphragm is attached, and this diaphragm is held at its periphery firmly
between the upper and lower parts of the separating drum. Upon the upper part of
the boss by which the diaphragm is carried upon the spindle, a milk-receiving cup
rosts. This cup is approximately hemispherical or conical in its internal contour, and
at its upper part it carries an internally projecting flange which is of such an external
diameter as to completely close or fill the mouth of the drum. The milk is fed into
this cap by a regulator. At suitable intervals round the upper part of the periphery
of this cup, a series of small holes are formed, through which the milk by centrifugal
action passes into the separating drum. The object of the internal flange hereinbefore
referred to is to permit of a sufficient head or pressure of milk being always maintained
by centrifugal action against these holes, and so causing solid streams of milk to
continually be forced through these holes, thereby preventing passage of air there-
through.
It is here explained that the rate of feeding is such, and the size of the holos is
such as to ensure this end being accomplished.
The milk on passing through the aforesaid holes in the receiving cup passes down
the conical interior of the upper part of the separating drum until it reaches the
bottom thereof, at which point the separated milk passes through a series of holes. at

page_text: or near the periphery of the diaphragm into the skim-milk collecting chamber.
Simultaneously with the passing out of the skim-milk, the separated cream floates
towards the bottom of one or more discharge guides, each of which consists of a
vertical or slightly inclined channel formed on the inner edge of each of the vanes
which are fixed inside the separating drum. Near the upper part of each of these
channels, a discharge orifice is situated, through which the cream passes by centrifugal
action into the annular collector which surrounds the machines, and from which it is
drawn off. Each of the channels hereinbefore referred to is formed to project inwards
at the top, so as to cause a solid body of cream to collect over the discharge orifices,
each of which is made small enough to prevent air passing through with the
cream.
The holes in the diaphragin through which the skim-milk passes, are made numerous
in order to prevent the eddying action which would take place if only a few holes were
used .therein.
The lip over which the skim-milk escapes, is varied in diameter in different machines
according to the rate and degree of soparation required, and fixed vanes may be used
in the skim-milk chamber, such as those horeinbefore described as being used in the
upper chamber, but without channels or guides. To the underside of the part of the
drum, and at a distance exterior to the discharge lip thereof, an annular collecting
chamber may be formed, into which the skim-milk passes by centrifugal action. From
this the milk is removed by a bent elevating pipe, or its equivalent, as is well
understood.
When it is not desired to remove the milk from the annular collecting chamber by
a pipe as aforesaid, the skim-milk overflows from this chamber by centrifugal action
into a fixed annular collector like that herein before described for collecting the
cream.
The aforesaid separating drum is so attached to its spindle as to be easily removed
therefrom for being washed or cleansed.
In order that our Invention may be properly understood and readily carried into
effect, we have hereunto appended one explanatory sheet of drawings in the several
figures of which, corresponding parts are marked with the same letters of reference.
Figure 1, is a vortical section of the separating drum, constructed in accordance
with our Invention.
Figure 2, shows a modified construction of the upper part of the separating drum,
with the cup by which the milk is fed into the separating drum.
Figure 3, is a section through a, b, of the discharge guide for the cream.
In the improved centrifugal machine as shewn at Figure 1, the upper part of the
drum is marked A, which is of the conical shape there shewn, and having the smallest
part of the cone uppermost. The lower end of this upper part of the separating drum
is formed with an external screw-thread, as shewn in the drawing, by means of which
it is attached to the lower part B, of the said dram. This lower part of the drum B,
has an inclined face leading to the discharge lip, and constitutes the skim-milk
collecting, and discharge chambers.
The two parts A, and B, are attached to the diaphragm C, by enclosing and firmly
securing the periphery of the said diaphragm C, between their two screwed portions.
The central portion of the diaphragm C, has a boss D, the hole in which is by
preference conical to correspond with and fit upon the upper conical end of the
spindle E. This boss is sufficiently long to ensure the separating drum being firmly
carried on the said spindle. The parts A, B, and C. D, of which the separating drum
is composed, are by preference made of steel forgings, and after being carefully formed
by being turned in a lathe, they are coated with tin, or other metal which has no action
on the milk or cream.
Within the upper part A, of the separating drum, the milk-receiving cup F, is
carried. This cup may be carried in several ways. In Figure 1, it is shewn as carried
on the upper part of the separating drum, while in Figure 2, it is shewn as being
carried on the upper part of the boss D. Whichever plan is adopted for carrying the

page_text: cup, the fitting between the cup and the drum must be accurately made, so that the
cup and separating drum must revolve together at the same time in such a manner as
that the cup may be removed when desired. The milk-receiving cup F, is made
with its largest diameter at, or near the top. It has an inwardly projecting flange G,
at the top, and at a sinall distance below this flange there is a row of small holes H,
bored completely through the cup, making a communication between the cup and the
upper part of the separating drum. Milk is supplied by the spout I, from the milk-
feeding chamber J.
As the milk passes into the cup F, the centrifugal force, due to the rapid rotation
of the cup, causes the milk to rise up the side of the cup to the top, and to press
against the flange G. The holes H, will thus be kept completely covered with a body
of milk in, the cup, and solid streams of milk will be forced through them into the
upper part of the separating drum, without any air being allowed to pass with the
milk. The centrifugal action of the separating drum causes the milk escaping into it
through the holes H, to move rapidly towards the lower part which is the part of
greatest diameter, and therefore the part moving with the greatest velocity. In
passing downwards, the milk and cream become separated, the cream coming inwards
towards the centre, and the skim-milk going outwards towards the largest diameter.
The cream and milk which have been separated from one another, are made to flow in
different directions, so as to escape from the drum for collection, in the manner now
to be described. The interior of the drum is fitted with one or more vanes K, which
project radially from the conical side of the drum towards its centre. One of those
vanes is shewn in section at Figure 3. Each of these vanes is provided at its inner
edge with a channel L, which is slightly inclined, so that the lower part is rather
nearer the axis of the separating drum than its upper part. There is a small space M,
between the lower part of each channel L, and the diaphragm C. Through this space
the floating cream passes to the bottom of the channel, and by centrifugal action
passes up the channel, and escapes through the hole N, into the annular collecting
chamber O, from which it is drawn off by the spout P.
The milk from which the cream has been separated and collected, as hereinbefore
described, passes through a series of small holes Q, which are provided at short
intervals all round the periphery of the diaphragm C, in continuous streams into the
lower part of the drum R, from which it escapes over the lip of the inclined surface S,
into the collecting chamber T. The milk may be taken from this chamber by being
allowed to flow over its lip U, into the annular receptacle V, and drawn off by the
spout W, or it may be caused by centrifugal action to pass into a collecting pipe X,
by which the milk may be conveyed to a receiver placed at any convenient distance.
The application and construction of such a pipe being well understood need not be
further detailed. The pipe X, is arranged so that the milk can be drawn away by
either of these methods. When it is desired to draw away the milk by means of the
pipe X, this pipe is in the position shewn in full lines; but when it is desired to draw
off the milk by the spout W, the nozzle of the pipe is brought nearer the axis of the
centrifugal machine, either by sliding it into the position shown by dotted lines, or by
turning the nozzle round. The nozzle is thus taken out of the milk, which is allowed
to flow over the lip U, into the annular receptacle V.
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 we are
aware that drums for centrifugal machines for separating milk from cream in which
there is an upper part, a lower part and a diaphragm secured together and connected
to the shaft by means of a boss have been proposed before the date of our application
for Patent and that our Invention is confined to the particular construction described
in our specification, and what we do claim is :-
1. In centrifugal machines for separating cream from milk, the construction of the
drum in three parts, namely, the upper conical part A, the lower part B, and the
diaphragm C, D, secured together and connected to the shaft by means of the boss D,
substantially as described and shewn on the drawings.

page_text: 2. The distributing cup F, constructed so as to prevent the passage of air along
with the milk, into the separating chamber, substantially as described, and illustrated
in Figures 1, and 2.
3. The discharge guides for the cream, constructed with a vertical or slightly
inclined channel, along which the cream flows to the discharge orifice, substantially as
described and shewn on-the-annexed drawings.
4. The annulir collecting chamber T, on the underside of the drum, into which the
separated liquid passes, and from which it can be drawn off by means of a bent tube
or its equivalent, substantially as described and shewn on the annexed drawings.
Dated this 29th day of April 1889.
JOHN LIDDLE,
154, St. Vincent Street, Glasgow,
Applicants' Agent.