IMPROVEMENTS IN SEPARATING OR REMOVING CREAM FROM MILK, AND IN THE MACHINERY OR APPARATUS TO BE EMPLOYED THEREIN
Year: 1879

page_text: LETTERS PATENT to Edwin Powley Alexander, of 14, Southampton Buildings,
in the County of Middlesex, Consulting Engineer and British and Foreign
Patent Agent, for the Invention of "IMPROVEMENTS IN SEPARATING OR
REMOVING CREAM FROM MILK, AND IN THE MACHINERY OR APPARATUS TO BE
EMPLOYED THEREIN." A communication from abroad by the Firm of
W. Lefeldt and Lentsch, of Schoningen, Braunsweig, in the Imperial German
Empire, Engineers.
PROVISIONAL SPECIFICATION left by the said Edwin Powley Alexander at
the Office of the Commissioners of Patents on the 24th December 1879.
EDWIN POWLEY ALEXANDER, of 14, Southampton Buildings, in the County of
Middlesex, Consulting Engineer and British and Foreign Patent Agent 'IMPROVE-
MENTS IN SEPARATING OR REMOVING CREAM FROM MILK, AND IN THE MACHINERY
OR APPARATUS TO BE EMPLOYED THEREIN." A communication from abroad by the
Firm of W. Lefeldt and Lentsch, of Schoningen, Braunsweig, in the Imperial German
Empire, Engineers.
The said Invention relates to improvements in centrifugal apparatus and the
mode of using or applying the same for effecting the separation or removal of cream
from milk in a peculiar intermittent or partially continuous manner, as hereinafter
described.
The centrifugal drum employed may be made with or without perforations or
openings through its sides and used with or without partitions. A ring cover is
employed which, by preference, is of such a construction and so fitted to the drum;
that the inner diameter of the drum shall be less than the inner diameter of the
cover itself just above the part where it joins the drum, thereby forming all round
the upper part of the drum an annular outward recess, of a depth at least equal to
the thickness of the side of the drum. The milk or heaviest portion of the liquid
naturally tends to collect within this recess or at the part farthest from the centre,
and hence a more powerful centrifugal action will be exerted upon that portion of
the milk which occupies the said recess. If desired, the drum and cover may be

page_text: formed without the said annular recess, or the recess may be made in the upper
part of the side itself of the drum. The outlets for the liquid are made, by
preference, through the cover of the drum and are so disposed as to take the said
liquid (milk or cream as the case may be) from the before mentioned annular recess
or from the upper or, if preferred, from the lower part of the interior of the drum
itself.
or
Above or below the ring cover or any other convenient part of the drum, I
sometimes adapt double or parallel discharge pipes or passages of a
equivalent shape, the bends of the said pipes or the inner junction between the two
parallel passages being situate slightly outside of or beyond the edge of the central
opening in the said ring cover. Both the passages may be above or below the
cover, or one above and one below; when situate below the cover the passage or
passages may pass out through the side of the drum itself.
According to one arrangement one of these double or parallel outlet pipes or
passages when placed above the cover opens downwards through the cover, by
preference, direct into the before mentioned annular recess, or in the absence of this
recess, into the upper part of the drum itself near its circumference and serves for
the escape of the skim milk as required, whilst the other passage extends beyond
the periphery of the cover so as to project over a surrounding annular collecting
chamber for the skim milk or the cream as may be required according to the mode
of working. This passage is provided with a separate communication from the
annular recess before mentioned, or from the upper part of the drum for the
discharge when required of the cream which has collected or accumulated in the
drum when working the apparatus in my improved intermittent or partially
continuous manner, as hereinafter described. In some cases single discharge
passages may be disposed at convenient intervals under the cover extending from
near the inner surface of the circumference of the drum or of the annular recess
back towards the inner edge of the ring cover where it communicates with a passage
through the cover and is provided with a cock or valve. The said discharge pipes
or passages are opened and closed more or less as required by a cock or valve
actuated by a lever mounted on or carried by the drum or its cover or otherwise
conveniently arranged. A curved lip over which the cream is discharged when
working continuously is formed as described in my Specification No. 2455, A.D.
1878, round the central opening in the ring cover, but such curved lip is not
absolutely necessary when the apparatus is working intermittently or in the partially
continuous manner, as will be hereinafter explained. The drum is provided with
any suitable arangement of feed tube or spreader inside which the new milk is
supplied and escapes under the lower edge thereof outwards to the periphery of the
drum.
When working the said apparatus in a continuous manner a constant and
regulated supply of new milk should be introduced through the spreader, the cream
produced therefrom collecting in an inner zone nearest the centre of the drum,
whilst the milk or liquid of greater specific gravity forms an outer zone at the
circumference of the drum, the cream being urged over the curved lip of the ring
cover into an annular cream collector, as described in the Specification to my Patent
No. 2455, A.D. 1878, the skim milk escaping at the same time through outlets
provided therefor and being collected in a separate annular or other milk collector.
Although the said apparatus is capable of working in a continuous manner I
prefer to work it in the intermittent or partially continuous manner which I shall
now describe, and wherein in lieu of the skim milk and the separated cream flowing
out simultaneously in distinct streams, the skim milk alone flows out of the drum
during the process of separation, leaving the cream behind to accumulate in the
drum and be discharged at the proper time. In working by this system a charge
of new milk is first introduced into the drum, of which charge a certain proportion
will consist of cream, which (when separated by centrifugal action) will take up
its position in the form of an inner vertical layer or zone of greater or less thickness

page_text: nearest the centre of the drum. More new milk is gradually run through the
drum from the centre outwards, the surplus milk escaping during the rovolutions in
the form of skim milk through the exit openings or outlets provided for that
purpose either in the upper, lower, or other convenient part of the drum, whilst the
cream is left behind to collect or accumulate within the drum. By the time the
additional supply of new milk has passed through the drum a proportionally
increased quantity of cream will be found to have accumulated or collected in such
drum until the drum is filled or partially filled with cream, which may be removed
or discharged at the proper time into a convenient annular receiver by opening a
valve or cock in the cream discharging apertures or passages; the drum being
thus emptied is ready for a fresh supply of new milk to be run through it without
stopping its revolution, and so on, the process of separating the cream being
continuous so long as the given quantity of milk is being supplied, or if preferred
in lieu of first charging the drum it may be started empty and the given quantity
of new milk run through it gradually from the commencement of the operation in
a continuous flow until the proportionate amount of cream which it contains has
collected or accumulated in and filled or nearly filled the drum.
The advantage of the partially continuous mode of working is that the cream by
being allowed to collect or accumulate quietly in the drum is less agitated than
when it is compelled to flow over the curved discharge lip in the cover as fast as it
is formed as in the continuous process, and the butter made therefrom is found to
be of a better keeping quality and consequently more suitable for exportation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edwin Powley Alexander in the Great Seal Patent Office on the 24th
June 1880.
EDWIN POWLEY ALEXANDER, of 14, Southampton Buildings, in the County of
Middlesex, Consulting Engineer and British and Foreign Patent Agent. "IMPROVE-
MENTS IN SEPARATING OR REMOVING CREAM FROM MILK AND IN THE MACHINERY
OR APPARATUS TO BE EMPLOYED THEREIN." A communication from abroad by the
Firm of W. Lefeldt and Lentsch, of Schöningen, Braunsweig, in the Imperial German
Empire, Engineers.
The said Invention relates to a peculiar mode or method of separating cream
from milk in centrifugal creaming machines, and to an arrangement of apparatus
for carrying out such mode of separation, and consists essentially in effecting the
separation of the cream from the milk by an intermittent or partially continuous
mode of working, wherein in lieu of as heretofore the skim milk and the separated
cream flowing off simultaneously in separate and distinct streams, the skim milk
alone flows out of the drum during its revolution, whilst the cream is left behind to
accumulate in the drum during the time that fresh new milk is being run through
until the drum becomes ultimately filled or nearly filled with creain alone, which
is removed at convenient intervals by a suitable arrangement of exit pipes or
otherwise, as will be hereinafter more fully described. It has been found in
practice that the less the cream is agitated the better will be the keeping quality of
the butter made therefrom, a most important desideratum when the butter is
required for exportation. Now the advantage accruing from the said intermittent
or partially continuous mode of working is that by allowing the whole of the cream
to collect or accumulate gradually and quietly in the drum during the time the
new milk is being run through the same it is subjected to less agitation than when
it is forced out of the drum by the action of the skim milk or other liquid of greater
specific gravity than cream as fast as it is being formed, as described in the
Specification to my Patent bearing date the 20th of June 1878, No. 2455. The
improved combination and arrrangement of parts constituting the centrifugal
creamer, which it is proposed to employ in carrying out the before mentioned
intermittent mode or method of separating cream from milk, but which may also, if
desired be used for effecting such separation by what is known as the continuous
process consists generally of a centrifugal drum, which may be made either with or
without perforations or openings through its sides, and be provided or not with
radial or other internal partitions. The said drum is provided with a ring cover,
which may be so constructed and fitted to the drum as to form all round the upper
part of the drum an annular recess of a depth at least equal to the thickness of the
side of the drum. Or the recess may be formed in the upper part of the side
itself of the drum or be entirely dispensed with if preferred. The milk or heaviest
portion of the liquid naturally tends to collect within this recess (when employed),
and consequently receives a more powerful centrifugal action by reason of its
increased distance from the centre of revolution of the drum. The outlets for the
liquid whether milk or cream as the case may be, are made by preference through
the cover of the drum, and are so disposed as to take the liquid from the before
mentioned annular recess (when used) or from the upper part of the drum itself
when not provided with the said recess.
Above or below the ring cover double discharge pipes or passages of a
or equivalent shape are by preference provided, the one limb or passage extending
inwards or back from near the periphery of the drum towards the edge of the
central opening in the drum cover, whilst the other limb or passage returns in an
outward direction over the periphery of the drum cover. The discharge end is

page_text: preferably turned downwards outside the periphery of the drum and cover, and the
junction between the two parallel passages is situate a short distance outside of or
beyond the edge of the central opening in the ring cover.
Both these passages
may be disposed above or below the cover, or one above and one below, but when
situate below the cover, the passage or passages may pass out through the side of
the drum itself, or at the bottom of the drum.
According to one arrangement, both the limbs of the said discharge pipe are
fitted to the upper surface of the cover, and open downwards by lateral passages
through the cover direct into the before mentioned annular recess or (in the
absence of this recess) direct into the upper part of the drum itself near its
circumference. One of these lateral passages opens into the outer end of one of the
two limbs of the double or
shaped discharge pipe, and serves for the escape
of the skim milk, the course of the milk being for a time back wards or towards the
centre of the drum, until it arrives at the junction with the other limb of the
discharge pipe along which it flows outwards, and is finally discharged through the
turned down end of the pipe which projects over a surrounding annular collecting
chamber for the skim milk or for the cream, as the case may be, according to the
mode of working the apparatus, as hereinafter explained. The second limb of the
shaped pipe is also connected near its outer end with the annular recess or
with the upper part of the drum by a separate lateral opening for the direct
discharge of the cream which has collected or accumulated in the drum when
working the apparatus in the improved intermittent or partially continuous
manner. One or both the limbs of the said discharge pipes or passages are opened
and closed more or less as required by a cock or valve actuated by a lever mounted
on or carried by the drum or its cover, or otherwise conveniently arranged. If
desired, a single in lieu of double discharge passage may be disposed at convenient
intervals under the cover extending from near the inner surface of the circum-
ference of the drum, or of the annular recess back towards the inner edge of the
ring cover, where it communicates with a passage through the cover, and is
provided with a regulating cock or valve. With a view to enabling the said
apparatus to be used when desired for effecting the separation of the cream and
milk by a continuous process, a curved lip is formed, as described in my said
Specification, No. 2455, A.D. 1878, round the central opening in the ring cover, but
such curved lip may be dispensed with when the apparatus is required for working
intermittently, or in a partially continuous manner. The drum is provided with
any suitable arrangement of feed tube and spreader arranged, by preference,
substantially in the manner described in my said Specification, inside which
spreader the new milk is supplied from a convenient feed pipe and cock, and
escapes under the lower edge of the spreader outwards to the periphery of the
drum.
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose shall refer
to the several Figures on the explanatory Sheet of Drawings hereunto annexed,
the same letters of reference indicating corresponding parts in all the Figures.
Fig 1 of my Drawings is a vertical section of one arrangement of the said
improved apparatus for separating and removing cream from milk by the improved
intermittent or partially continuous mode or method of working, but which is also
shown as adapted for effecting such separation by a continuous process if desired.
Figs. 2, 3, and 4, are enlarged details of the
shaped or double discharge
pipes or passages and regulating valve shown in Fig. 1. Figs. 5, 6, and 7, are
details hereinafter described, showing a modified arrangement of such discharge
pipes, and mode of working the same. In all these Figures I have represented the
drum as provided with the annular recess before referred to, but I do not confine
or restrict myself to the use of such recess, as the same may be dispensed with if
preferred, without interfering with the peculiar intermittent mode or method of
working which constitutes the essential feature of this Invention.
a is the outer fixed casing of the machine; b, the vertical drum spindle working

page_text: in a footstep bearing c, and driven by a strap and pulley d, or in any other con-
venient manner. Upon this spindle is mounted the centrifugal drum e, the boss of
which supports in any convenient manner the central revolving spreader f. The top
of the drum is fitted with a ring cover g, which may, if desired, though not
necessarily be so formed and fitted onto the drum as to leave between the
upper edge of the drum and the cover an annular recess h of larger diameter than
the inner diameter of the main body of the drum itself, as is more clearly shown in
the enlarged details. i is a lip curving outwards and formed round the edge of
the central openings in the drum cover; k is an annular inclined plate or surface
along which passes the outflowing cream which is forced over the said lip by the
action of the skim milk or other liquid of greater specific gravity than cream, as set
forth in my said former Specification, when working in a continuous manner;
Z is an outer annular collector, m are discharge spouts opening into convenient
receptacles; n is the top cover plate. If intended solely for working intermittently
or in a partially continuous manner then the lip i, the annular inclined plate or
surface k, and the outer annular collecting chamber 1 may be dispensed with.
o and o¹ (Fig. 4) are or syphon shaped tubes or double dischaige passages
fitted onto the ring cover, the bend or junction at p between the two limbs or
passages being situate slightly beyond or outside the inner edge of the central
opening in the ring cover, as is clearly shown in Figs. 2 and 4. One of the limbs o
of the
shaped tubes or passages opens downwards through the cover at q,
see Fig. 3, into the annular recess h, or simply into the upper part of the drum if
the said annular recess be not employed, whilst the other limb or passage o¹ extends
beyond the periphery of the cover into the inner annular milk collector r provided
with discharge sports s (sec Fig 2); t is another branch outlet from the upper part
of the drum provided with a valve u leading into the outer end of the limb of of
the double discharge passage, and opened or closed during the revolutions of the
drum by any convenient mechanical arrangement, as, for example, by a lever v, the
inner end of which may engage with a vertical sliding collar won the upper end of
the spreader f, which collar is free to be raised or lowered by a hand lever or other-
wise without stopping the drum, as will be readily understood on referring to Fig. 1.
The detail, Fig. 2, is a vertical longitudinal section of the limb o¹ taken along the
line 1-2 in Fig. 4, which is a plan and partial horizontal section of one of the bent
shaped or double discharge tubes or passages, and a portion of the ring cover
to which it is attached. Fig. 3 is a longitudinal vertical section of the other limb o
taken along the line 3-4 in Fig. 4.
The following is the mode of using the said apparatus for the purpose of carrying
out my improved intermittent or partially continuous mode or method of separating
the cream from the milk:-
Supposing the full or new milk to contain 10 per cent. of cream, for example, and
that the capacity of the drum up to the vertical line x-y corresponding to the
positions of the bends or inner junctions p of the double discharge passages, be 100
quarts, a charge of, say, 100 quarts of new milk is first introduced through the
spreader finto the drum by the feed pipe fitted with a regulating cock. Of this
charge 10 quarts will consist of cream, which (as it is separated by centrifugal
action) will take up its position and begin to collect in the drum in the form of an
inner vertical zone nearest the centre, such zone extending inwards as far as the
vertical line x-y, and reaching from the bottom of the drum up to the cover.
Then 900 more quarts of new milk are gradually run through the drum in a con-
tinuous flow from the interior of the spreader outwards to the circumference of the
drum. The skim milk escapes through the opening at q and along the double
passages o, o¹, in the top of the ring cover, it being discharged from the end of the
limb o' into the annular skim milk collector r. By the time the additional 900
quarts of new milk have passed through the drum 90 additional quarts of cream
(making 100 quarts in all) will be found to have accumulated in and filled or
partially filled the drum, and this cream may be discharged direct or by the nearest
way into the collector 7 by opening the valve u. The drum thus emptied is ready

page_text: for a fresh charge of new milk, and so on, the process being only continuous so long
as the given quantity of new milk (say, for example, 1000 quarts) is being run into
or through the drum. If desired the drum may be started empty, and the 1000
quarts of new milk run through it gradually in a continuous flow until the 100
quarts of cream which it contains will have accumulated in and filled the drum.
If it be desired to work the said apparatus in a continuous manner then a
constant and regulated supply of new milk should be introduced through the
spreader at the centre of the drum, the cream produced therefrom forming an
inner zone nearest the centre of the drum, whilst the milk or liquid of greater
specific gravity forms an outer zone at the circumference of the drum and forces
the cream as it is separated over the lip i of the ring cover and along the plate k
into the outer annular cream collector 1, whence it flows through the spouts m into
convenient receptacles, the skim milk escaping at the same time through the outlets
at g and along the passages o, o¹, and being collected in the separate annular milk
collector r, whence it flows away by the spouts 8.
In the modified arrangement of the shaped or double discharge pipes or
passages, shown in enlarged vertical section at Fig. 5, and horizontal section at
Fig. 6, a cock u¹ is substituted for the valve u in Fig. 1. The plug of this cock
passes transversely across the passages o and o¹, and is provided with a three way
opening at 1 and a transverse opening at 2 (Fig. 6). When the plug is turned so as
to bring the three way opening into the position shown in Fig. 5 the skim milk will
flow out of the drum through the opening at q along the passage o first towards the
centre of the drum and then back towards the circumference along the passage o' and
through the transverse opening 2 in the cock, escaping by the discharge nozzle into
an annular collecting chamber, leaving the accumulated cream alone (when working
intermittently) behind in the drum. The discharge nozzle is bent or turned down as
shown in order to prevent undue splashing of the liquid in the collecting chamber.
Now in order to discharge the accumulated cream and thus empty the drum the
cock u is simply turned a quarter of a revolution, bringing the three way opening 1
into the position shown in Fig. 7, and connecting the interior of the drum directly
with the turned down cream discharging nozzle, through which the cream flows by
the nearest way into the annular collecting chamber r. The point of junction p
between the two parallel discharge passages is situate a short distance beyond the
inner edge of the central opening in the drum cover as before described.
v is a
lever for turning the cock without stopping the revolution of the drum. If it be
desired to work continuously then the cream as it is formed is urged over the lip i
and down the plate k, as before explained, whilst the skim milk passes off through
the exit passages o, o¹. The improved intermittent or partially continuous
mode of working may be carried out if desired by the aid of a single discharge
passage and regulating cock o, as shown in sectional detail at Fig. 8, provided the
opening of the cock be large enough to allow all the influx milk to escape through
it leaving nothing to pass round the lip or edge i of the drum cover, or the same
effect may be produced by suitably regulating the influx of the milk into the drum.
Thus by allowing the heavier parts of the skim milk to escape continuously through
the discharge pipe o the drum will, according to the improved intermittent mode of
working, be gradually filled with cream up to the position of the dotted line x-y,
but some convenient mode of removing or discharging such cream is required, and
this can be best accomplished by the arrangements of double passages and valves or
cocks, as herein before described. It is true such accumulated cream might be
discharged over the lip i by allowing skim milk or other liquid of greater specific
gravity than cream to enter the drum, but in that case the cream becomes again
mixed more or less with the skim milk.
If (for the continuous discharge of skim milk, and at the same time, separation
of the cream from the skim milk) the exit openings were to lead directly outsido
instead of back towards the centre first, as in the arrangement of
shaped
or double discharge pipes or passages before described, the influx new milk with its

page_text: cream in it would flow out at once without leaving sufficient time for the separation
of the cream from the milk.
Figs. 9 and 10 represent in sectional elevation and plan a simple mode of drawing
off the skim milk or the cream from the revolving drum by means of a horizontally
pivotting or swinging tube attached to the top cover plate. A is a long arm of a
tube and B a shorter curved arm both connected and swinging horizontally on a
fixed centre C in the top cover n, the shorter tubular arm B being inside the
drum, and its end brought towards the centre or circumference thereof (as shown
in Fig. 10), according as cream or skim milk or nothing is to be removed, the same
being applicable either in the continuous mode of working the creamer or in
the improved intermittent mode of working. This arrangement may be used in
combination with or independently of the arrangements shown in the other Figures
of the Drawing.
I would here observe that I do not claim generally the working of centrifugal
cream separators in a continuous manner, and although I have shown that the said
apparatus may be worked either continuously or intermittently I prefer for the
reason aforesaid to work it in the intermittent or partially continuous manner
herein before fully specified.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original, and
therefore claim as the Invention secured to me by the hereinbefore in part recited
Letters Patent is,―
First. The peculiar mode or method of effecting the separation of cream from
milk by what I call the intermittent process in centrifugal creaming machines, that
is to say, when the said centrifugal machines are so arranged and worked as that
the whole of the skim milk shall be allowed to flow out of the drum when separated,
leaving the cream alone behind to accumulate in the drum until it has filled or
nearly filled the same, substantially in the manner and for the purpose hereinbefore
described.
Secondly. The combination and arrangement of parts constituting a centrifugal
creaming apparatus, substantially as hereinbefore described and illustrated by
Figs. 1, 2, 3, 4, 5, 6, and 7 of the Drawings hereunto annexed.
Thirdly. The combination or arrangement of parts constituting a centrifugal
creaming apparatus in combination with the additional apparatus for drawing off
the milk and cream or either of them, substantially as herein before described and
illustrated in Figs. 9 and 10 of the Drawings hereunto annexed.
In witness whereof, I, the said Edwin Powley Alexander, have hereunto
set my hand and seal, this Twenty fourth day of June, in the year of
our Lord One thousand eight hundred and eighty.
DWIN D AT VANDED