Improved Apparatus for Determining the Relative Percentages of the Fluid Components of a Compound Fluid.
Year: 1893

page_text: GUMI DID DT MOITICATION.
Improved Apparatus for Determining the Relative Percentages of
the Fluid Components of a Compound Fluid.
I, PETER VRAA POVLSEN BERG, of 18 Rorholmsgade, Copenhagen, in the
Kingdom of Denmark, 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 :—
My invention relates to improvements in apparatus for determining percentages
of the component fluids in a compound fluid, and is particularly useful for determining
the percentage of cream in milk.
It consists in the combination of a closed annular box or drum, annular trays,
test tubes arranged radially in as many divisions thereon with their closed ends
outwards, and radial ridges or dividing strips separating the tubes from each
other, the whole adapted to be rotated at a high velocity by any suitable means.
In order that the invention and the best means of carrying it into practical effect
may be thoroughly understood, I will now describe it and them in detail, referring
in so doing to the accompanying figures which are to be taken as part of this
Specification and read therewith.
Fig. 1 is a horizontal section of an apparatus made according to my invention.
Fig. 2 is a vertical section along the line A-B of Fig. 1.
a b is an open annular box or drum. It is made of any suitably strong material
and, preferably, with the two sides a, b and the bottom c in one piece, as illustrated.
It is circular in plan because it will be revolved at a high velocity, and annular
for the purpose of facilitating its being made fast to the shaft with which it
is to be revolved. In point of dimension the diameter of the box is greater than
its depth.
d is the detachable cover. It fits within the top of the box or drum a flush
therewith, resting upon a seat d' which may be formed in either side of the box.
e is a nut threaded to fit the central screwed nozzle a¹. The latter is a continuation of
the inner box side b. Its function is to hold the cover d down upon its seat. f,fare
detached annular trays. They fit the interior of the drum and are provided with a
set of radial ridges or dividing strips g. The latter are arranged symmetrically
upon the trays at a proper distance apart to receive a test tube m between each
adjacent pair of such ridges or strips. The tubes lie with their open ends towards
the axis of rotation, while their closed ends rest in seatings provided by any
suitable device, e.g., by as many pairs of vertical plates h, h. The ridges or strips y
stand up from the respective tray for a distance of a little more than the diameter
of a test tube so that the latter lie within their respective divisions. The depth of
the drum is so arranged that a given number of trays will just fill it, the cover d
touching the ridges or strips g of the top one when it is held down on its seat d'.
This method of arranging the contents of the drum provides for the test tubes
retaining their position with reference to the axis of rotation irrespective of the
plane of the latter, and also for confining the fracture of a tube to its own division.
In the latter case the other tubes on the same tray are not exposed to the impact
of the broken pieces, nor are they free to move out of their position or to be thrown
against each other.
My invention is used as follows:-The tubes are filled with the fluid to be
operated on, laid in the divisions, the trays placed in the drum, the cover screwed
down, and the whole set revolving. The proper rate of rotation varies according
to circumstances. One of from 5000 to 7000 revolutions per minute is the proper
one when milk is being tested to determine its value as a source of butter.
The centrifugal energy very soon drives the heavier portions outwards from the

page_text: axis of rotation; and the lighter portions—the cream, if milk is being tested-are
collected in the mouths of the test tubes, i.e., near the axis where the energy is
weaker than near the periphery of the drum.
The separation of the component fluids is effected in a few minutes. The drum
is then opened, the tubes taken out and set up in a stand in the order which they
occupied in the drum, and the heights of either or both columns estimated by an
apparatus specially constructed for the purpose.
Special gearing for rotating the drum and its contents is provided and may be
of any suitable type, or the drum may be mounted upon the shaft of an ordinary
centrifugal separator.
The plane of separation between the heavier and the lighter liquid is so well
defined in the tubes, that it becomes possible to forthwith determine accurately the
length of the space which the lighter liquid occupies, and from that to determine
the relative percentages.
With my invention, the data for numerous determinations are taken at once
under circumstances common to all the samples under examination, so that there is
a great economy in time. Further, as the tubes are always radial, they are in the
best possible position for resisting the strain to which they are subjected by the
centrifugal energy.
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 :-
The combination in apparatus for determining by centrifugal energy the relative
percentages of the fluid components of a compound fluid, of a drum or box, a series
of. trays fitting therein and radial dividing strips dividing each tray up into
radial divisions, each adapted to receive a test tube and fitted to confine it to
one position therein, the said trays occupying the entire interior of the drum or
box, as set forth.
Dated thin 10th 1.- of Fahr 1900