Improvements in Filtering or Straining Apparatus for use in Pipes, Mains, or Conduits conducting Gas, Steam, Air, or other Fluids under Pressure.
Year: 1898

page_text: Date of Application, 30th Apr., 1898-Accepted, 4th June, 1898
Improvements in Filtering or Straining Apparatus for use in Pipes,
Mains, or Conduits conducting Gas, Steam, Air, or other Fluids
under Pressure.
I, MAX MORIZ JAENNIGEN, of VI Magdalenenstrasse 46, Vienna, in the Empire of
Austria, Engineer, do 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 :-
In filters or strainers for fluids under pressure the parts thereof nearest to
the inlet are liable to be stopped or clogged, first, by the bodies which it is desired
to filter or strain off, thereby bringing about a reduction of pressure at the side of
the filter opposite the inlet. The time during which a filter of this construction
remains in proper working order is therefore short and a fresh filter has soon to be
substituted for the one in use. Now in order to effect this without interrupting the
operations in progress and without allowing the fluid to carry away with it, any of
the impurities of which it is proposed to cleanse it by filtering, the arrangement of
a number of filtering discs or diaphragms such as f¹ f2 f³ &c. placed one above the
other and preferably assuming the shape of truncated cones, has proved to be
extremely serviceable. The diaphragms are secured to a central spindle S are turned
true at their outer periphery, and are fitted within a cylinder C after the manner of a
plunger or piston. In this arrangement, assuming that the orifice, admitting the
fluid to be filtered, is situated under the lowermost one of the series of
filters f f f &c. the lowest of these f¹ will first become charged with impurities.
If for example the working pressure prevailing in the chamber R be eight atmo-
spheres; then, in consequence of the filter becoming charged with impurities, the
pressure in the compartment R¹ will fall below eight atmospheres-say as low as seven
atmospheres. By drawing down the filter f¹ however, into the compartment R, so
that the filter f2 now takes the place of the filter f¹, equality of pressure in front
and behind the filter f2 will be restored, immediately the filter f¹ leaves the
operative" part of the cylinder C. The process is repeated as many times as may
be necessary, the remaining filters f2, f³ f* &c. being thus lowered each in
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succession.
The filter whether f¹, f2, fs, or any other-which happens at the time to have
thus been lowered into the compartment R, may be cleansed by the fluid that is to
be filtered and is supplied under pressure, say by opening the purge valve or cock H;
in which case the fluid, by reason of the truncated cone-shape of the filters f¹ f2 &c.,
will traverse such filters in the opposite direction, which in the case of Figure 1 will
be a downward direction, since in its proper "operative" or filtering course, the said
fluid takes an upward direction. In thus descending, the fluid will accordingly
loosen and remove the impurities from the under sides of the filters, and carry them
out of the chamber R through the purge-cock or valve H. When the whole or part
of the series of filters, according to requirements, has thus been cleansed, the same
filters may be refitted in the operative position within the cylinder C as before, no
exchange of filters being necessary; and the filtering process may be started afresh,

page_text: while equality of pressure-being a desideratum for many practical purposes is
ensured in the manner herein before described.
The successive displacement of the filters fi ƒ ƒ³ &c. may-as illustrated in
Figure 1, be effected by means of a handle G, fitted to the outwardly extended
spindle S or it may be caused to take place automatically as shown in Figure 2.
The diminution of pressure occurring behind the filters f f f³ &c. on clogging of
the filter taking place being made use of for the purpose of actuating a piston or
plunger K arranged to reciprocate in a cylinder C¹, which communicates with the
cylinder C both below and above the filters f f f &c. The cross sectional area
of the cylinder c¹ is made greater than that of the cylinder C so as to bring greater
surface pressure to bear on the said piston K. The piston K will in each case shift
for a distance 81 82 83 &c. exactly equal to that existing between the successive
filters f f f &c.; and it stops whenever one of the said filters f¹ f2 f³ has descended
from the interior of the cylinder C into the purifying chamber R, at which moment
the desired equality of pressure is restored in front of and behind the piston K. The
piston K is connected to the filtering arrangement by means of the links g g¹ and
the double lever h h¹ pivotted at c. When the piston K is fully raised it may be
made to strike an electrical contact and thereby cause an alarum or call-bell A to
ring, to notify to the attendant that the cleansing of the filters f¹ƒ ƒ³ &c. in the
manner described should now be proceeded with.
Pressure gauges M. and M¹ enable the pressures reached in front and behind the
series of filters f¹ f2 f³ &c. and also the operative pressures existing in front of and
behind the piston K, respectively, to be read off, while an index-hand or pointer a
may be used to indicate on a scale b the position occupied by the filtering bodies at
the time.
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
1. Filtering or straining apparatus for pipes, mains or conduits conducting steam,
air, gas, or other fluid under pressure the said apparatus mainly consisting of a
number of filtering bodies, such as f f f &c. inserted into a service pipe, main or
conduit, and supported on a spindle S, one above another, so that they can be moved
into and from a cylinder or chamber C, the arrangement being such that the filter
which becomes charged with impurities, can be removed into a cleansing chamber
such as R, so that the diminution of pressure, which would otherwise take place, as
the impurities collect on the filtering material, is obviated without any interruption
in the filtering operation and without any of the bodies to be filtered off being
carried away by the filtered fluid, and the filters at the same time can be cleansed as
aforesaid.
2. In combination with an arrangement such as is claimed by the first claim, a
spindle S, provided at one end with a handle G and at the other with an index-hand
such as a adapted to slide along a scale b.
3. In combination with an arrangement such as is claimed by the first claim, a
piston K interposed between the chamber R¹, which receives the filtered fluid, and
the chamber R, receiving the fluid to be filtered, and connections by which the
motion, which is imparted to such piston by reason of the difference of pressures in
the chambers R and R¹ is transmitted to the filtering bodies.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.