Note: Descriptions are shown in the official language in which they were submitted.
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ASSEMBLY FOR PROCESSING A FLUID BY FILTRATION AND
CENTRIFUGATION
A fluid treatment assembly is known, which assembly comprises, a filter
which itself comprises one or more filtering elements and a device for
periodically
cleaning each filtering element including on the one hand, a rotary
distributor
which periodically isolates one part of the filtering surface of each
filtering
element in order to enable the counter-current cleaning thereof, and on the
other
hand, an evacuation conduit for the cleaning fluid filled with the impurities
resulting from the cleaning, said treatment assembly further comprising a
centrifuging treatment device which itself comprises a rotary centrifuging
enclosure connected to a cleaning fluid admission conduit.
In this known treatment assembly, the centrifuging treatment device is
separated from the filter and is connected therewith via conduits external to
each of
said two treatment and filtering devices.
Such a treatment assembly is bulky, its cost price is high and it is subject
to
accidents, particularly where the external connection conduits are concerned.
It is the object of the present invention to overcome said drawbacks by
proposing to integrate, inside a single casing, the two devices which had been
separate up to now.
Thus according to the invention, the filtering element or elements and the
centrifuging enclosure are contained in a single casing, while the evacuation
conduit for the cleaning fluid filled with impurities issues directly into the
admission conduit of the rotary enclosure.
The advantageous following dispositions are also preferably adopted:
- one end of one of the evacuation conduits is fitted in one end of the other
of said two conduits, while the other end of the admission conduit is fixed on
said
single casing;
- said other end of the admission conduit is fixed to said casing via a bolt
which, at the same time, obturates said other end;
- the centrifuging enclosure communicates with the inside of the casing via
at least one outlet nozzle for the centrifuged fluid, which nozzle is oriented
substantially perpendicularly to a radius passing through the axis of rotation
of said
centrifuging enclosure, in such a way that said centrifuging enclosure is
driven in
rotation by the reaction of the fluid coming out of said outlet nozzle or
nozzles
with respect to the fluid contained in the casing;
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- said evacuation conduit is provided in the rotaty distributor;
- receiving chambers for receiving the fluid filtered by the filtering
elements
of the filter and the fluid treated by the centrifuging treatment device, are
provided
in said single casing, said chambers being separated one from the other by a
fluidtight partition wall.
The invention offers the following main advantages : compactness of the
treatment assembly, reliability of said assembly, and reduced production costs
compared with the prior constructions.
The invention will be more readily understood and secondary characteristics
and their advantages will emerge from the following description of one example
of
embodiment.
It is to be understood that the description and drawings are only given by
way of indication and non-restrictively.
Reference will be made to the accompanying drawings, in which
- Figure 1 is an axial section of a treatment assembly according to the
invention,
- Figure 2 is a section along II-II of Figure 1, and
- Figure 3 is a section along III-III of Figure 1.
The fluid treatment assembly illustrated in the figures comprises a filter and
a centrifuging treatment device, both of them being contained in a single
casing 1
made up of two parts lA,1B, assembled by bolts.
The filter, which is contained in part lA of the casing, comprises:
- two transversal end walls 2, 3 between which is provided a stack 4 of
filtering elements 5, each one of which is shaped into a filtering disk 9,
with two
screens 6;
- a central axis 7;
- aligned bores 8, having the same diameter, and being coaxial to axis 7,
each bore belonging to one of the filtering disks 9, in tight contact with the
cylindrical external face 10 of a liner 11, which liner comprises a bore 15 co-
axial
to the axis 7;
- a central fluid distributor 12, mounted for rotation about axis 7, in tight
contact with a bore 13 provided in the intermediate wall 2, said wall being
itself
tightly assembled to parts lA and 1B of the casing;
- a U-section sector 14, provided in the fluid distributor 12, the periphery
16
of which bears tightly against the bore 15 of the liner 11, and which
communicates
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with an evacuation conduit 17 provided in the fluid distributor 12, coaxial to
axis
7;
- a driving fork 18, situated at the axial end of the fluid distributor 12
opposite the intermediate wall 2;
- a receiving chamber for receiving the filtered fluid 19, which chamber is
provided inside the part lA of the casing, contains the stack 4 of filtering
elements
5 and is equipped with a connector 20 for the evacuation of the filtered
fluid;
- an admission chamber 21 for admitting the polluted fluid to be filtered,
said chamber being equipped with an admission connector 22 for admitting the
fluid to be filtered;
- a motor 23, in this particular example, a hydraulic motor, for driving the
fluid distributor 12 in rotation, said motor being fixed on the part lA of the
casing
and being equipped with a driving member 24 operationally coupled to the fork
18
for driving the fluid distributor 12 in rotation.
Each filtering element 5 comprises a plurality, counting twelve in the
embodiment illustrated in Figure 2, of angular sectors 41 which, through
orifices
provided in the liner 11 and in the bores 8, are adapted, successively, to
create a
communication between the inside space 27 defined by the parts of the two
screens
6 of the sector considered, and a conduit 26 which is provided in sector 14 of
the
20 fluid distributor 12 and which issues into the evacuation conduit 17, which
latter is
a blind conduit at the end of the fluid distributor 12 facing the wall 2.
The centrifuging treatment device is contained in part 1B of the casing and
comprises
- a central admission conduit 28 for admitting the fluid to be centrifuged, of
25 which one end 29 is constituted by an endpiece fitted in the open (non-
blind) end
of the evacuation conduit 17, while the other end 31 is constituted by a
female
thread for fixing in an obturating bolt 32; the bolt 32 itself constitutes the
end of a
plug 33 screwed 34 into a transversal end plate 35 which defines, in part 1B
of the
casing, a chamber 36 for receiving the centrifuged fluid, which chamber is
tightly
30 separated from the chamber 19 receiving the filtered fluid, by the
intermediate wall
2;
- a centrifuging enclosure 37 is mounted for rotating, via rings forming
smooth bearings, about axis 7, which axis 7 is also the axis of the admission
conduit 28 and of its external face 28A, said conduit therefore forming also a
rotary shaft for the centrifuging enclosure 37;
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- orifices 38 creating a communication between the admission conduit 28
and the inside 39 of the enclosure 37.
A transversal bottom 40, which is perpendicular to the axis 7, defines the
part
of the centrifuging enclosure 37 which is placed in facing relationship to the
transversal wall 2. Said centrifuging enclosure 37 is totally isolated from
the
receiving chamber 36 receiving the centrifuged fluid except for the
communication
created by two outlet nozzles 43, which are substantially diametrically
opposite,
and whose outlet orifices are directed so as to be substantially perpendicular
to a
diameter passing through the axis 7, and in two opposite directions.
The treatment assembly works as explained hereinbelow.
The fluid to be treated, which is admitted into the admission chamber 21,
fills in the inner spaces 27 of all the sectors of the various filtering
elements 5, with
the exception of the space inside the sector 41 of each filtering element
which is
temporarily isolated from the other sectors 41 by the U-section sector 14
which is,
itself, in communication with the conduit 26.
This fluid to be filtered, which is contained in said spaces 27, flows through
the screens 6 of said sectors, depositing on the inner faces thereof, the
impurities
that it contains, and being received when cleared of its impurities, into the
receiving chamber 19 receiving the filtered fluid which is ready to be used
again.
Conversely, as regards the sectors 41 of the various filtering elements which
only communicate with the conduit 17, the pressure of the already filtered
fluid
which is contained in the chamber 19, causes part of said fluid to flow
through the
corresponding parts of the filtering screens 6, this enabling the impurities
which
have deposited on the inner faces of the screens to be periodically detached
therefrom and to be driven into the evacuation conduit 17. The function of the
motor 23 is to drive stepwise, sector 41 by sector 41, the distributor 12 in
rotation
so as to ensure that each angular sector 41 of the various filtering elements
is
periodically placed in communication with the evacuation conduit 17.
Said fluid filled with impurities is conveyed directly via the evacuation
conduit 17 and the admission conduit 28 towards the centrifuging enclosure 37,
where it is received therein 39 and where, by centrifuging, it is cleared of
its
impurities. The purified fluid is then evacuated out of the enclosure 37
through the
nozzles 43 and is received into the chamber 36 wherefrom it is released
towards an
application unit, via an outlet connector 44 provided in part 1B of the
casing.
It should be observed that the rotation of the centrifuging enclosure 37 is
induced by the effect of reaction, with respect to the fluid contained in the
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enclosure 37, of the fluid escaping from the inside 39 of the enclosure 37
through
the conduits 42 of the nozzles 43. Said reaction effect is sufficient to drive
the
centrifuging enclosure in rotation at a rotation speed - of the order of 6000
rpms -
at which the centrifuging is effectively perfonmed. As a reminder, the speed
of
5 rotation reached by the motor 23 is around 2 to 3 rpms.
The advantage of the described embodiment resides in the compactness and
light weight of the assembly; in the elimination of any leaks from the
external
connections between Alter and centrifuging device, due to the elimination of
said
external connections; in the elimination of any risks of the external conduits
breaking up, as these conduits have also been eliminated; and finally, in the
obtained reduction of the assembly manufacturing costs..
It is understood that the invention is not limited to the embodiment of
filters
equipped with disks or pads as filtering elements, but also covers the case of
any
other filters such as, for example, those having cylindrical screens. The
motor 23,
which is advantageously a hydraulic type motor, may also, as a variant, be of
another type, such as electric. Finally, at least one nozzle 43 should be
provided,
and preferably an even number of diametrically opposite nozzles.
The invention finds an application in the treatment of lubricating oils for
"Diesel" type engines, or even in the purification of certain fuels used by
said
engines.
The invention is not limited to the described embodiment, and on the
contrary covers any variants that can be made thereto without departing from
its
scope or its spirit.
