Year: 1886

page_text: I, ERNST PABST, Student of Natural Sciences, of Hannover, in the Empire of
Germany, do hereby declare the nature of my invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement and accompanying drawing (that is to say):
If a vessel or vat be filled with pure milk, the fat or butter, on account of its
lower specific weight as compared with the remaining ingredients, will rise to the
upper part, and if at the bottom of the vessel or vat is fitted an ordinary cock,
there will flow on opening it, first poor or thin milk, and last the pure fatty part
or butter.
This is recognized as an inconvenience, especially for the consumers of milk
coming from large milk establishments, in cities.
The object of the mixing cock which forms the subject of my present invention
is to avoid this fault.
The accompanying drawing is in illustration of my invention.
An ordinary cock is applied to the lower part of a milk-vessel; it does not
terminate directly on the inner side of the vessel, but is continued to the upper
part of the vessel in the form of a tubular prolongation, of circular or conical form,
or the tube may be adapted to the cock in such a way, as is represented by
Figure 2, that is to say, the outlet of the pipe placed inside the vessel is of a
conical shape, and corresponds with the inner end of an ordinary cock or other
regulating outlet.
The pipe or tube inside the milkvessel is perforated with a certain number of
holes, which are bored in any convenient way, in a spiral or circular form. The
diameter of these holes may be equal or unequal, according to the effect which it is
desired to produce.
Supposing the holes to be of equal diameter or size, then no milk will flow out
of the vessel itself, but only from the tube, because the level of the milk in the tube
and in the vessel remains in the ordinary state at all times the same;
the pressure
on both sides of the holes being also the same, the latter may be considered
as inert.
The level of the milk inside of the tube will sink therefore, by drawing off milk
through the cock.

page_text: The equilibrium of pressure inside and outside of the tube becomes destroyed,
and every hole will come into a certain amount of play under the influence of the
altered pressure, which corresponds with the difference between the pressure inside
the tube and that inside the vessel.
An automatic regulating movement therefore takes place operated by the raising
and lowering of the surface in the tube, so that milk flows from the vessel into the
tube, according to the quantity which is drawn off by opening the cock. Each
hole receives, according to their diameters and the pressure in them, so much milk
from each layer of milk in the vessel, as there are holes in the tube, so that mixed
milk will directly flow out through the cock.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
An ordinary cock, with one or more prolongations in form of tubes inside a milk
vessel, to its upper end, which tubes are provided with holes of equal or different
diameters and sizes, in any height or position, the said arrangement having for its
object the drawing off of a liquid, simultaneously from different horizontal layers
in a liquid vessel or vat.