Year: 1888

page_text: We, HEINRICH GEHRKE, Manufacturer, and ADOLF WOHLFAHRT, Engineer, both
of 3 and 4 Zimmerstrasse Berlin, in the Kingdom of Prussia and Empire of
Germany, 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 :-
The object of the invention is certain improvements in filtering apparatus, of which
the following is a full and clear specification, reference being had to the accompanying
drawings, which form a part of the specification and in which similar letters denote
corresponding parts.
The invention relates to a filtering apparatus used in drawing beer from the tuns
into small casks, and its object is not only to free the beer of any heterogeneous bodies,
but to provent, during the process of drawing off, the loss of carbonic acid and the
formation of foam, removing at the same time any atmospheric air which may be
contained in the beer. The apparatus may also be used advantageously for drawing
off or filtering other fluids.
In the drawings
=
Figure 1 is a vertical axial section of the apparatus.
Figure 2 is
front elevation thereof.
Figure 3 is a partial plan.
In this filter the leading principle is to offer to the fluid, from the moment of its
entrance, a space or chamber increasing gradually in width until the fluid encounters
at last the proportionally extended filtering material, passing it very slowly and
at all points with the same energy. By this arrangemant the formation of canals
or ways in the filtering material, so injurious to the effect of the filtering, is fully
obviated.
The atmospheric air which may be contained in the beer must be removed
before the beer enters the filter proper, which is done by a separate automatic air
remover.
After leaving the filter proper the beer passes the antifoamer, a small vessel, by the
peculiar construction of which any foam which might be formed is destroyed, and any
atmospheric air which might be contained in the filtering material, or emitted from
the beer by any other cause, is removed, so that the beer will fill the small cask clear,
devoid of foam and airless.
Figure 3 is a partial plan.
In this filter the leading principle is to offer to the fluid, from the moment of its
entrance, a space or chamber increasing gradually in width until the fluid encounters
at last the proportionally extended filtering material, passing it very slowly and
at all points with the same energy. By this arrangemant the formation of canals
or ways in the filtering material, so injurious to the effect of the filtering, is fully
obviated.
The atmospheric air which may be contained in the beer must be removed
before the beer enters the filter proper, which is done by a separate automatic air
remover.
After leaving the filter proper the beer passes the antifoamer, a small vessel, by the
peculiar construction of which any foam which might be formed is destroyed, and any
atmospheric air which might be contained in the filtering material, or emitted from
the beer by any other cause, is removed, so that the beer will fill the small cask clear,
devoid of foam and airless.

page_text: For the purpose of eliminating, during the filtering process, those substances which
require a certain temperature for their separation, means are provided to keep the
filtoring vessul at this required temperaturo In arranging the pipe line between the
Lun and the cask, care is taken that sharp bends or corners do not occur. To facilitate
the cleaning, and to obtain the last drop of filtered beer, the filtering device can be!
tilted or turned upside down. The beer (or other fluid), in entering the apparatus
through the pipe or hose n, passes the air removor m, flows from below through the
filter drum b, leaves it at its top for the antifoamer k, and travels from the latter
through pipe into the cask, or any other vessel of destination.
The air romover m consists of an upright vessel, the upper part of which is made
of a glass cylinder u clamped tightly between the hollowed cover to and the cup shaped
lower part u, into which flows the beer through the pipe n² from the hose n, which
parts are united by the pipe coupling n'. The cover io has a contral hole communi-
cating with the lip valve provided upon the top of the cover w. From the lowest
point of the part the elbow pipe s' forms the outlet for the beer. Inside of tho air
remover m is contained a rubber ball of such specific gravity that it will float upon
the beer if the apparatus is in action. If the beer commences to enter the nir
remover m, the ball e closes the outlet opening so that the boor will fill the whole
apparatus, but cannot pass into the elbow pipes. To allow its passage the ball is
pushed from its seat by the pin t, being forcibly thrown upward, whereupon it will
rise to the cover we closing the passage to the lip valve e. Any atmospheric air
contained in the fluid will also bubble up to the cover te and there accumulate until
the pressure of the air becomes strong enough to lower the surface of the fluid in the
vessel u whereupon the ball will sink also, opening the passage to the lip valve,
through which the air now passes until its reduced pressure and quantity allows the fluid,
and with it the ball z, to rise again. so that the ball closes again the passage to the lip
valve. It is clear that these operations continue as long as air has to be expelled. If
the operation of drawing off the beer is at its termination, the ball x sinks down upon
the opening of the elbow pipe s, closing it tightly so that no air can follow into it, the
pin, working through a stuffing box, having boen drawn back automatically by a
spring, after it had been pushed upward. This sudden push is given to the pin
the hammer thrown up by a sudden pressure of the foot of the attendant upon tho
free end of the lever t. The hammer and the lever are mounted upon the bed
frame of the filter. The air remover m may be placed in any convenient
position, but it is preferably mounted on one of the standards or frames o of the
filter.
by
The beer flows from the air romover m through the elbow pipe s' and the sleeves,
to which it is connected by a short flexible hose, and through a cock h and elbow
pipe into the filter. The sloevo s is connected to the cock by a union.
The filter proper consists of the following parts:
1. The urn shaped jacket supported by, and swinging round, the trunnions z,<¹,
which rost in boarings in the standards or frames o, o, mounted upon the bed frame p.
The trunnion a¹ is hollow.
2. The filter chambor a, which is contained within the jacket f, at its lowor narrow
portion a ponetrates such jacket, and is jointed by a stuffing box to the elbow pipo .
Un top it rosts with a wide flange a upon a reinforce of the jacket to which it is
secured by bolts or scrows. It is closed by a cover d, which is only a little convox and
has in its centre an opening not larger than the other beer conduit or pipes to which
is jointed an elbow pipe g' with cock g. The cover d is tightened by easily manipu-
Inted screws upon the flange a² which possesses a number of hand holes a³ closed by
caps. On the underside of the cover d an annular rib is provided fitting into the filler
chamber a and bearing slightly upon the filter drum b.
3. The filter drum & with flat perforated siove like bottom and top lid is of nearly
cylindrical shape corresponding to the filter chamber a, to which it fits snugly. The
sides or barrel of the drum are or is made of sheet metal and not perforated. The
whole filter drum b rests upon an offset a' of the filter chamber a and is kept in position
'by the annular rib above mentioned of the cover d. To avoid a deflection of the lid

page_text: of the drum 6 a number of rubber cushions or supports d' are arranged between these
two parts. The filter drum b is filled with any suitable filtering material. The space
of the filter chamber a below the filter drum b is filled with insoluble inatorial, such as
wood shavings, boiled straw, etc., for distributing the beer uniformly over the whole
area of this space.
4. To the cock g is jointed the bent pipe; tightened by a pipe union to a branch
pipe of the hollow trunnion 2. To the free end of this trunnion is attached the
pipe of the antifoamer k by means of the stationary bridge, in such way that
tho trunnion 2¹ is free to revolvo without moving the pipe i and without interrupting
the tightness of the joint of the pipe i and the hollow trunnion s².
b
The beer entering the filter chamber a through the narrow entrance a* spreads out
as it rises in the space below the filter drum b gradually more and more and therefore
moves slower and slower, so that it enters finally the filter drum 6 very slowly but
with a uniform force and velocity over its entire surface. By means of this construction,
and the peculiar inverted bell-like shape of the filter chamber a, the great drawback
of other filters is avoided, in which the fluid enters as a stream of small area directly
into the filtering material without sufficient room to spread, and in which the force of
the fluid forms, in the filtering material, canals or ways, by which the fluid passes
through the filter very rapidly but proportionally poorly filtered.
As glucose and other substances can be eliminated only at a certain low temperature,
and as it is desirable generally to work the beer cold, the jacket f is wholly or partially
filled, through the hand holes as with ice or a frigorific mixture, according to circum-
stances, which, after use, may be drawn off by the cock f. For other fluids, which
require a certain high temperature the jacket may contain warm water or even steam
during the filtering process.
The beer, after having passed the filter drum b, flows through the outlet of the
cover d, the elbow pipe gl, the cock g, the pipe j, the hollow trunnion 2¹ and the pipe i
into the antifoamer k, which latter may be erected separate from the filter proper at
any convenient place, but which is preferably mounted upon a bracket from the
frame o, as represented in the drawing.
The antifoamer & consists preferably of a closed vessel & with its long axis arranged
vertically, into which enters the pipe i, in such way that its open ond is directed down-
ward near the lower part of the vessel ¹. For the discharge of the beer the pipe /
is employed, of which that portion inside the vessel k¹ is bent trap-liko, so that its
mouth is turned upwards. Any foam or air carried along by the beer will, from the
outlet of the pipe i, rise, through the boer filling the vessel to the top of the latter.
During this time the beer foam will be reabsorbed by the beer, but not also the air.
To expel it, the vessel is connected by the piper to the air remover m², constructed
in manner similar to that vessel m which the beer had to pass prior to its entering
the filter proper. The glass cylinder is confined between two plates, to the lower
one of which is secured the pipe r, and the upper one (the hollowed cover w) is
provided with the lip valve communicating with the interior of the cylinder u.
The ball floating upon the beer will let out the air accumulated at the upper part
of the air remover m² as soon as its pressure is strong enough to depress the surface
of the beer and will close the passage to the lip valve v if the beer rises again, as
before explained in relation to the air remover.m. Should all the beer foam not be
re-absorbed in the vessel k¹ it will also pass into the air remover and be re-absorbed
in this way.
Through the pipe the beer flows into the cask (not shown in the drawing) or any
other suitable receptacle. As that quantity of the beer which is contained in the
filter chamber a cannot flow further, if the ball x of the air remover m³ has closed the
conduit from the tun, and as it should be saved, the cock h is shut, the union between
this cock and the pipe s unscrewed and the whole filter turned upside down round
the trunnions z, z. After opening again the cock h most of the beer in the filter
chamber a will flow off through the pipe and the rest can be obtained also by being
forced forward by water filled into the filter chamber a through the cock h. In this
way the loss of beer is reduced to an insignificant portion.

page_text: The two standards or frames o are mounted upon the bed frame which is made
of wood or better (as represented) of iron. It can be turned round the central
vertical pin g' of the truck 7 which is provided with four low wheels. To facilitato
this turning motion friction rollers are interposed between the frame p and the
truck q. By constructing the support or foundation of tho filter in a similar manner
to a turntable on whools, the wholo apparatus can be run into the narrow passages
between the tuns of the collar, which it would be impossible or at least very difficult
to enter without such provisions and it can be used in the direction most convenient
for the drawing off manipulation.
It is well known that there are in existence filtering apparatus for beer and other
fluids but they are constructed in a different manner and upon other principles and
there are also used air removers with air cocks or metallic valves and also anti-
foamers of a more complicated and expensive arrangement and I would have it
understood that these dovicos in their woll known constructions are not claimed.
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed we declare that what I claim is :-
1. A filtering apparatus for beer and other fluids in which the entering fluid is
compelled to pass, prior to encountering the filter proper, a chamber gradually
increasing in width, whereby the velocity of the fluid is decreased proportionally so
that the fluid enters the filter proper and passes it with the same energy and
simultaneously over the whole area of the filter proper substantially as herein described
and for the purpose explained.
2. A filtering apparatus for bear and other fluids consisting of a filtering chamber a
with a narrow entrance at for the fluid at its bottom and increasing gradually in
width to the top, which chamber contains the filter drum b, is closed by the cover d
having a narrow outlet opening, and is surrounded by the jacket and supported upon
tho trunnions, in bearings of frames o constructed and operating substantially
as shown and described and for the purpose set forth.
3. A filtering apparatus as covered by claim 2 in combination with air removers m, m³
according as the fluid enters from below or from the side consisting of the vessels u
and u the floating ball and the lip valve v, and with the anti-foamer & consisting of
the vessel & the inlet pipe i of which opens downward and the entrance of the outlet
pipo which is of syphon shape and is directed upward, arranged and constructed as
shown and described and working as explained.
4. The combination of the anti-foamer k and tho air romover m² connected by the i
tuber for the purpose specifiod.
5. The air remover in provided with the pin & drawn back by a spring, in com-
bination with the hammer and the lever tactunting the hammer substantially as
shown and for the purpose set forth.
6. The filtering apparatus as covered by claim 2 supported in bearings of thos
frames o and supported upon trunnions 2, 3, in combination with the bed frame p
turning round the pin 7' of the wheeled truck g substantially as shown and described
and for the purpose explained.
Daind this 30th day of June 1900