[0001] The invention relates to a sucking apparatus, in particular for cleaning, for example
arranged for sucking fragments of material or objects of small dimensions.
[0002] A sucking apparatus according to the preamble of claim 1 is already known e.g. from
WO-A-2010121656.
[0003] Known sucking apparatuses comprise one or more filters and one or more sucking motors.
The filter is interposed between the external environment and the sucking motor for
filtering the flow of air sucked by the sucking apparatus. The filter, positioned
inside a collecting tank, retains here the sucked material, such that only clean air
reaches the sucking motor.
[0004] After a certain number of hours of operation of the sucking apparatus the filter
has to be cleaned, otherwise it no longer permits the air to pass, which reaches the
motor only in extremely reduced quantities or even nothing. This thus compromises
the operation of the apparatus, which is thus not usable until the filter is cleaned
or replaced with a new filter.
[0005] Accordingly, in known sucking apparatuses it is necessary for the operator, i.e.
the person who usually uses the sucking apparatus, to clean the filter.
[0006] In order to clean the filter, the operator can dismantle the filter from the sucking
apparatus and then shake and hit the filter energetically in order to remove the material
that has previously been deposited thereupon. This material is generally released
into the surrounding environment and so this method of cleaning the filter is not
advisable because the material released into the environment is again sucked by the
sucking apparatus with the result that the filter will again get dirty very rapidly.
[0007] Alternatively, known sucking apparatuses can comprise air-channelling systems comprising
pressure switches and/or deviator valves that convey a flow of air to the filters
so as to clean the filters.
[0008] One drawback of these sucking apparatuses is that they are rather complex, and thus
costly, due to the presence of the air channelling systems and of the deviator valves.
[0009] One embodiment of these apparatuses provides for these air channelling systems being
driven by the operator. One drawback of this embodiment is that the apparatus cannot
ensure complete and reliable filter cleaning. Effective filter cleaning in fact substantially
depends on the time that the operator dedicates to cleaning the filter. One serious
drawback of these apparatuses is the fact that cleaning the filter is manually driven
by the operator, who, - typically because of lack of time or negligence - does not
dedicate sufficient time to ensure thorough removal of the material deposited on the
filter.
[0010] One object of the invention is to improve known sucking apparatuses.
[0011] Another object of the invention is to supply a sucking apparatus in which the filter
is cleaned completely automatically.
[0012] A further object of the invention is to supply an efficient sucking apparatus that
does not need to be stopped for filter cleaning operations and at the same time ensures
good cleaning of the filter.
[0013] According to the invention, a sucking apparatus is provided as defined in claim 1.
[0014] The invention can be better understood and implemented with reference to the attached
drawings, which show an embodiment thereof by way of non-limiting example, in which:
Figure 1 is an exploded view of a sucking apparatus according to the invention in
which some elements have been removed for the sake of clarity;
Figure 2 is a perspective bottom view of a portion of the sucking apparatus in Figure
1;
Figure 3 is an enlarged perspective view of a valve element comprised in valve means
of the sucking apparatus in Figure 1;
Figure 4 is an exploded schematic perspective view of a portion of the sucking apparatus
in Figure 1 shown in an operating configuration by way of example.
[0015] With reference to Figure 1 there is shown a sucking apparatus 1, in particular for
cleaning. The sucking apparatus 1 can be a vacuum cleaner, for example of the professional
and/or industrial type.
[0016] The sucking apparatus 1 comprises at least two sucking motors 10 arranged for generating
a flow of air F from the outside to the inside of the apparatus.
[0017] The sucking apparatus 1 further comprises at least two filters 17 arranged upstream
of the sucking motors 10 for filtering the flow of air F in such a manner as to retain
on the filter the sucked material, such that substantially clean air reaches the sucking
motor 10. The filters 17 are positioned inside a collecting tank (which is not shown)
where the sucked material is retained, such that only clean air reaches the sucking
motor 10.
[0018] Each filter 17 is associated with a respective sucking motor 10. It should be noted
that in Figure 1 for the sake of clarity only one sucking motor 10 and one filter
17 are shown.
[0019] The sucking apparatus 1 further comprises a base 14 that supports the sucking motors
10. A supporting element 16 on which the filters 17 are fixed is connected to the
base 14 on a side opposite the sucking motors 10. The base 14 is thus interposed between
the sucking motors 10 and the filters 17. The sucking apparatus 1 can comprise, for
example, three sucking motors 10 and three filters 17.
[0020] The sucking apparatus 1 comprises valve means 13 interposed between, and operationally
associated with, each sucking motor 10 and each filter 17. The valve means 13, comprises,
for example, three valve elements 23, each of which is received in a respective seat
21 made on the base 14. The valve elements 23, for example the same as and independent
of one another, are movable between a rest position R (shown in Figure 1), in which
they are housed in the seats 21 (visible in Figures 2 and 4), and a raised position
S (Figure 4), in which they are raised from the respective seats 21. This occurs when
the sucking motor 10 associated with the valve element 23 is working, as will be explained
in greater detail below with particular reference to Figure 4. When a valve element
23 is in the raised position S it allows the passage of the flow of air F prevalently
along a direction indicated by the arrow A in Figure 1.
[0021] Each sucking motor 10 can be axially aligned along a direction that is substantially
parallel to the first direction A, to a valve element 23 and to a respective filter
17.
[0022] In alternative embodiments of the invention, each sucking motor can be not aligned
axially on the valve element 23 and on the filter 17 associated therewith, provided
that the motor, the valve element and the filter are arranged in such a manner as
to be traversed in sequence by the same flow of air.
[0023] With reference to Figure 3, a valve element 23 is visible which has been significantly
enlarged.
[0024] The valve means 13, in particular each valve element 23 comprised therein, is provided
with a calibrated passage 20 arranged for enabling, when the valve means 13 is in
the rest position R, the passage of at least one portion F' of the flow of air substantially
along a second direction B, opposite the first direction A, from the sucking motor
10 to the filter 17 for cleaning the latter.
[0025] The calibrated passage 20 is suitably sized in such a manner as to enable, on one
hand, the passage of a flow of air F that is suitable for ensuring good sucking capacity
of the sucking apparatus 1, and on the other hand, to enable a suitable portion F'
(Figure 4) of the flow of air to reach the filter 17 to clean the filter 17. In other
words, the calibrated passage 20 has dimensions that are such as to enable a portion
F' of the flow of air to reach a filter 17 and clean the filter without there being
a loss in sucking capacity of the apparatus 1.
[0026] The valve element 23 comprises a base portion 23a, for example disc-shaped, and a
plurality of flaps 23b, for example eight flaps 23b that are angularly equidistant
at an edge of the base portion 23a. The flaps 23b are arranged for defining a suitable
thickness for enabling the passage of the flow of air F when the valve element 23
is in the raised position S.
[0027] The calibrated passage 20, for example shaped as a circular hole, can be made substantially
at a central zone of the base portion 23a (i.e. substantially at the centre of the
disc).
[0028] In an alternative embodiment of the invention, the base portion 23a can have any
other shape than the disc shape, for example a square shape or any other polygonal
shape. When the valve element 23 is in the rest position R the base portion 23a abuts
on the surface of the base 14 such as to ensure that the valve element 23 remains
inside the seat 21 thereof.
[0029] The sucking apparatus 1 comprises a locking element 8 (Figure 1), fixed to the base
14, and in which a plurality of cavities 24 are made that are aligned on the seats
21 parallel to the first direction A. The sucking apparatus 1 thus comprises a number
of cavities 24 that is equal to the number of seats 21. Each cavity 24, on one side
receives an end of a sucking motor 10, and on the other side is shaped as a conduit
that projects to the base 14, in particular to the seat 21 underneath. The locking
element 8 thus enables the sucking motors 10 to be stopped, and, owing to the cavities
24 that act as a guiding element for the valve elements 23 - the valve means 13 to
be moved between the rest position R and the raised position S.
[0030] The sucking apparatus 1 further comprises a cover 4 that, together with the base
14, bounds a chamber in which the sucking motors 10 are positioned.
[0031] Inside this chamber different known elements of the sucking apparatus 1 are positioned,
such as, for example, a soundproofing element 12 - arranged for reducing the noise
produced by the sucking motors 10 that spreads outside the apparatus - or a cover
7 for the sucking motors 10.
[0032] With the cover 4 a plurality of known elements are further associated such as, in
particular: a pushbutton 6 for switching on and switching off the apparatus, a handle
5 for carrying the apparatus, an electric cable 2 (provided with a cable gland 3)
to supply the apparatus.
[0033] The sucking apparatus 1 can further comprise a plurality of wheels (not shown) owing
to which the operator can position the sucking apparatus 1 in the desired position.
[0034] The operation of the sucking apparatus 1 will now be explained with reference to
Figure 4.
[0035] In the sucking apparatus 1, two sucking motors 10 are always working, whilst the
remaining third sucking motor 10 is not working.
[0036] For this purpose, the sucking apparatus 1 comprises an electronic control unit U,
for example an electronic card, which has been schematised in Figure 4. The control
unit U is further programmed for controlling the sucking motors 10 in such a manner
that at least one of the sucking motors 10 is stopped and the remaining sucking motors
10 are operational. The electronic control unit U thus drives the three sucking motors
by suitably combining switch-ons and switch-offs of the latter. In particular, the
electronic control unit U controls the sucking motors 10 according to preset cyclical
temporal sequences such that in successive work cycles of the same duration, the sucking
motors 10 are stopped in sequence one after the other. Therefore, in the embodiment
of the sucking apparatus 1 disclosed above and shown in Figure 4, in which there are
three sucking motors 10, the electronic control unit U drives the apparatus 1 by repeating
over time three different successive work cycles, during each of which a different
sucking motor 10 is stopped.
[0037] The valve elements 23 positioned respectively below the two sucking motors 10 that
are working are maintained in the raised position S. In Figure 4, the distance of
the two valve elements 23 in a raised position S from the respective seats 21 has
been emphasised for the sake of clarity and the movement of the valve elements 23
has been indicated by the arrows S1 and S2. The third valve element 23, arranged below
the non-working sucking motor 10 is in the rest position R. When a non-working sucking
motor 10 is driven by the electronic control unit U, the valve element 23 arranged
below the motor goes from the rest position R to the raised position S owing to the
vacuum created by the sucking motor. On the other hand, when a working sucking motor
is stopped, the vacuum created by the motor stops suddenly and the underneath valve
element 23 moves from the raised position S to the rest position R.
[0038] The two working sucking motors 10 thus create a vacuum inside the collecting tank
of the sucked material. A flow of air F is thus created that is sucked inside the
apparatus 1 and which, after having passed through the two filters 17 arranged below
the working motors, passes through the seats 21 and enters the chamber in which the
sucking motors 10 are arranged. From here, a portion F' of the flow of air passes
through the calibrated passage 20 of the valve element 23 which is in the rest position
R, so as to be directed to the third filter 17, i.e. the filter arranged below the
non-working sucking motor (on the left in Figure 4). This third filter 17 is then
cleaned by the portion F' of flow of air, which is clean air inasmuch as it was previously
filtered by the remaining two filters 17 arranged below the two working sucking motors
10.
[0039] Owing to the presence of the calibrated passages 20, which enable the sucking motor
10 to be obtained constantly in communication with the respective filter 17 associated
therewith, it is possible to clean in turn the filters 17 of the sucking apparatus
1 in a completely automatic manner. In fact, whilst the sucking apparatus 1 is in
operation, stopping in turn one of the three sucking motors 10, it is thus possible
to clean effectively the filter associated with the non-working sucking motor 10 without
this reducing the flowrate of the flow of air F sucked by the apparatus 1. One advantage
of the sucking apparatus 1 is to make available automatic cleaning of the filters
17 with which the apparatus is provided without this reducing the performance of the
apparatus in terms of vacuum and flowrate of the sucked air. In fact, the portion
F' of flow of air that cleans the filter 17 is already included in the flow of air
F found inside the sucking apparatus 1.
[0040] Another advantage of the sucking apparatus 1 is that the filters 17 are cleaned during
normal operation of the apparatus.
[0041] A further advantage is that cleaning of the filters no longer depends on the time
that the operator dedicates thereto, as it is no longer performed manually by the
operator but automatically by the apparatus.
[0042] Still another advantage consists of the fact that the sucking apparatus 1 has lower
structural complexity and manufacturing costs than those of known apparatuses, or
at the limit structural complexity and manufacturing costs that are comparable with
those of known apparatuses. In fact, the sucking apparatus 1 does not require any
external system, in particular it requires neither pipes, nor solenoid valves nor
diverter valves for the air that would make the apparatus 1 more complex and costly.
[0043] A still further advantage is that the filters 17 of the sucking apparatus 1 are more
durable and must therefore be replaced significantly less often than known apparatuses.
Owing to this, the time that the operator has to dedicate to checking the state of
cleanliness of the filters 17, and to replacing the filters 17 is significantly less
than known apparatuses.
[0044] In alternative embodiments of the invention a different number of sucking motors
10, of filters 17 and of valve elements 23 can be provided, as long as one sucking
motor 10 is always associated with a respective filter 17 and a respective valve element
23 is placed therebetween that maintains the sucking motor 10 and the filter 17 always
in reciprocal communication owing to the presence of a calibrated passage 20.
[0045] Possible variations and/or additions are possible to what has been disclosed above
and/or shown in the attached drawings.
1. Sucking apparatus (1), in particular for cleaning, comprising:
- at least two sucking motors (10) arranged for generating a flow of air (F) from
the outside to the inside of said apparatus (1);
- at least two filters (17) arranged upstream of said sucking motors (10) for filtering
said flow of air, each filter (17) being associated with a respective sucking motor
(10);
- valve means (13) interposed between, and operationally associated with, each sucking
motor (10) and each filter (17), characterised in that said valve means is movable between a rest position (R) wherein said valve means
(13) is received in respective seats (21), and a raised position (S), wherein said
valve means (13) is raised from said respective seats (21) when the sucking motor
(10) associated therewith is working, to enable the passage of said flow of air (F)
prevalently along a first direction (A);
wherein said valve means (13) is provided with a calibrated passage (20) arranged
for enabling, when said valve means (13) is in said rest position (R), the passage
of at least one portion (F') of said flow of air substantially along a second direction
(B), opposite said first direction (A), from said sucking motor (10) to said filter
(17) for cleaning said filter (17).
2. Apparatus according to claim 1, comprising an electronic control unit (U) arranged
for controlling said sucking motors (10) such that at least one of said sucking motors
(10) is stopped and the remaining sucking motors (10) are working.
3. Apparatus according to claim 2, wherein said electronic control unit (U) controls
said sucking motors (10) according to preset cyclical temporal sequences such that
said sucking motors (10) are stopped in sequence one after the other in successive
work cycles.
4. Apparatus according to claim 3, wherein said work cycles have the same duration.
5. Apparatus according to any preceding claim, wherein each sucking motor (10) is axially
aligned, along a direction that is substantially parallel to said first direction
(A), to a valve element (23) comprised in said valve means (13) and to a respective
filter (17).
6. Apparatus according to any preceding claim, wherein said calibrated passage (20) is
sized in such a manner as to enable a portion (F') of said flow of air to reach said
filter (17) and clean said filter (17) without there being a loss in the sucking capacity
of the apparatus.
7. Apparatus according to claim 5 or 6, comprising a base (14) in which said seats (21)
for said valve elements (23) are made.
8. Apparatus according to claim 7, comprising a locking element (8) fixed to said base
(14) and arranged for locking said sucking motors (10).
9. Apparatus according to claim 8, wherein said locking element (8) comprises a plurality
of cavities (24) aligned on said seats (21).
10. Apparatus according to claim 9, wherein said cavities (24) are shaped as conduits
and arranged for acting as guiding elements for guiding the movement of said valve
means (13) between said rest position (R) and said raised position (S).
11. Apparatus according to any one of claims 7 to 10, wherein said at least two sucking
motors (10) are supported by said base (14) and enclosed in a chamber bounded by said
base (14) and by a cover (4) of said sucking apparatus (1).
12. Apparatus according to any one of claims 7 to 11, wherein said filters (17) are fixed
to a supporting element (16) connected to said base (8).
13. Apparatus according to any preceding claim, comprising three sucking motors (10),
three valve elements (23) and three filters (17).
1. Saugvorrichtung (1), zum Reinigen, mit:
- zumindest zwei saugenden Motoren (10), die zum Erzeugen eines Luftstromes (F) von
der Außenseite zur Innenseite der Vorrichtung (1) angeordnet sind;
- zumindest zwei Filtern (17), die stromabwärts der saugenden Motoren (10) zum Filtern
des Luftstromes angeordnet sind, wobei jeder Filter (17) einem jeweiligen saugenden
Motor (10) zugeordnet ist;
- Ventilmitteln (13), die zwischen jedem saugenden Motor (10) und jedem Filter (17)
angeordnet und mit diesen in Wirkverbindung stehen, dadurch gekennzeichnet, dass die Ventilmittel zwischen einer Ruhestellung (R), in der die Ventilmittel (13) in
jeweiligen Sitzen (21) aufgenommen sind, und einer abgehobenen Stellung (S) beweglich
sind, in der die Ventilmittel (13) von den jeweiligen Sitzen (21) abgehoben sind,
wenn der ihnen jeweilig zugeordnete saugende Motor (10) arbeitet, um den Durchgang
des Luftstromes (F) vorherrschend entlang einer ersten Richtung (A) zu ermöglichen;
wobei die Ventilmittel (13) mit einem kalibrierten Durchgang (20) versehen sind, der
dazu angeordnet ist, den Durchgang zumindest eines Anteils (F') des Luftstromes im
Wesentlichen entlang einer zweiten Richtung (B), die der ersten Richtung (A) entgegengesetzt
ist, von dem saugenden Motor (10) zu dem Filter (17) zum Reinigen des Filters (17)
zu ermöglichen, wenn die Ventilmittel (13) in der Ruhestellung (R) sind.
2. Vorrichtung nach Anspruch 1, mit einer elektronischen Steuereinheit (U), die zum Steuern
der saugenden Motoren (10) angeordnet ist, derart, dass zumindest einer der saugenden
Motoren (10) angehalten ist und die übrigen saugenden Motoren (10) arbeiten.
3. Vorrichtung nach Anspruch 2, wobei die elektronische Steuereinheit (U) die saugenden
Motoren (10) gemäß voreingestellten zyklischen zeitlichen Abfolgen steuert, derart,
dass die saugenden Motoren (10) in Reihenfolge einer nach dem anderen in aufeinanderfolgenden
Arbeitszyklen angehalten sind.
4. Vorrichtung nach Anspruch 3, wobei die Arbeitszyklen dieselbe Dauer aufweisen.
5. Vorrichtung nach irgendeinem vorherigen Anspruch, wobei jeder saugende Motor (10)
entlang einer Richtung, die im Wesentlichen parallel zur ersten Richtung (A) ist,
mit einem Ventilelement (23), das die Ventilmittel (13) aufweisen, und mit einem jeweiligen
Filter (17) axial ausgerichtet ist.
6. Vorrichtung nach irgendeinem vorhergehenden Anspruch, wobei der kalibrierte Durchgang
(20) in seiner Größe derart bemessen ist, dass ein Anteil (F') des Luftstromes den
Filter (17) erreichen und den Filter (17) reinigen kann, ohne dass ein Verlust an
Saugkapazität der Vorrichtung auftritt.
7. Vorrichtung nach Anspruch 5 oder 6, mit einer Basis (14), in der die Sitze (21) für
die Ventilelemente (23) ausgebildet sind.
8. Vorrichtung nach Anspruch 7, mit einem Absperrelement (8), das an der Basis (14) festgelegt
ist und zum Absperren der saugenden Motoren (10) angeordnet ist.
9. Vorrichtung nach Anspruch 8, wobei das Absperrelement (8) eine Mehrzahl an Hohlräumen
(24) aufweist, die an den Sitzen (21) ausgerichtet sind.
10. Vorrichtung nach Anspruch 9, wobei die Hohlräume (24) als Kanäle geformt und zum Wirken
als Führungselemente zum Führen der Bewegung der Ventilmittel (13) zwischen der Ruhestellung
(R) und der abgehobenen Stellung (S) angeordnet sind.
11. Vorrichtung nach irgendeinem der Ansprüche 7 bis 10, wobei die zumindest zwei saugenden
Motoren (10) von der Basis (14) gehalten und in einer Kammer eingefügt sind, die von
der Basis (14) und durch eine Abdeckung (4) der Saugvorrichtung (1) begrenzt ist.
12. Vorrichtung nach irgendeinem der Ansprüche 7 bis 11, wobei die Filter (17) an einem
Tragelement (16) festgelegt sind, das mit der Basis (8) verbunden ist.
13. Vorrichtung nach irgendeinem vorhergehenden Anspruch, mit drei saugenden Motoren (10),
drei Ventilelementen (23) und drei Filtern (17).
1. Appareil de type aspirateur (1), utilisé notamment pour le nettoyage, comprenant :
- au moins deux moteurs d'aspiration (10) agencés pour générer un flux d'air (F) de
l'extérieur vers l'intérieur dudit appareil (1) ;
- au moins deux filtres (17) agencés en amont desdits moteurs d'aspiration (10) pour
filtrer ledit flux d'air, chaque filtre (17) étant associé à un moteur d'aspiration
respectif (10) ;
- des moyens de valve (13) interposés entre, et fonctionnellement associés à, chaque
moteur d'aspiration (10) et chaque filtre (17), caractérisé en ce que :
lesdits moyens de valve sont mobiles entre une position de repos (R) dans laquelle
lesdits moyens de valve (13) sont reçus dans des sièges respectifs (21), et une position
soulevée (S), dans laquelle lesdits moyens de valve (13) sont soulevés desdits sièges
respectifs (21) lorsque le moteur d'aspiration (10) associé est en fonctionnement,
pour permettre le passage dudit flux d'air (F) principalement dans une première direction
(A) ;
dans lequel lesdits moyens de valve (13) sont pourvus d'un passage calibré (20) agencé
pour permettre, lorsque lesdits moyens de valve (13) sont dans ladite position de
repos (R), le passage d'au moins une portion (F') dudit flux d'air sensiblement dans
une deuxième direction (B), à l'opposé de ladite première direction (A), à partir
dudit moteur d'aspiration (10) vers ledit filtre (17) pour nettoyer ledit filtre (17).
2. Appareil selon la revendication 1, comprenant une unité de commande électronique (U)
agencée pour commander lesdits moteurs d'aspiration (10) de sorte qu'au moins l'un
desdits moteurs d'aspiration (10) est arrêté et les autres moteurs d'aspiration (10)
fonctionnent.
3. Appareil selon la revendication 2, dans lequel ladite unité de commande électronique
(U) commande lesdits moteurs d'aspiration (10) selon des séquences temporelles cycliques
préréglées de sorte que lesdits moteurs d'aspiration (10) sont arrêtés séquentiellement
l'un après l'autre selon des cycles de travail successifs.
4. Appareil selon la revendication 3, dans lequel lesdits cycles de travail ont la même
durée.
5. Appareil selon l'une quelconque des revendications précédentes, dans lequel chaque
moteur d'aspiration (10) est axialement aligné, selon une direction qui est sensiblement
parallèle à ladite première direction (A), avec un élément de valve (23) que comportent
lesdits moyens de valve (13) et avec un filtre respectif (17).
6. Appareil selon l'une quelconque des revendications précédentes, dans lequel ledit
passage calibré (20), est dimensionné de manière à permettre une portion (F') dudit
flux d'air d'atteindre ledit filtre (17) et de nettoyer ledit filtre (17) sans que
cela occasionne une perte de la capacité à aspirer de l'appareil.
7. Appareil selon la revendication 5 ou 6, comprenant une base (14) dans laquelle lesdits
sièges (21) pour lesdits éléments de valve (23) sont réalisés.
8. Appareil selon la revendication 7, comprenant un élément de verrouillage (8) attaché
à ladite base (14) et agencé pour verrouiller lesdits moteurs d'aspiration (10).
9. Appareil selon la revendication 8, dans lequel ledit élément de verrouillage (8) comprend
une pluralité de cavités (24) alignées sur lesdits sièges (21).
10. Appareil selon la revendication 9, dans lequel lesdites cavités (24) ont la forme
de conduits et sont agencées pour servir comme éléments de guidage pour guider le
déplacement desdits moyens de valve (13) entre ladite position de repos (R) et ladite
position soulevée (S).
11. Appareil selon l'une quelconque des revendications 7 à 10, dans lequel lesdits au
moins deux moteurs d'aspiration (10) sont supportés par ladite base (14) et enfermés
dans une enceinte délimitée par ladite base (14) et par un couvercle (4) dudit appareil
de type aspirateur (1).
12. Appareil selon l'une quelconque des revendications 7 à 11, dans lequel lesdits filtres
(17) sont attachés à un élément de support (16) connecté à ladite base (8).
13. Appareil selon l'une quelconque des revendications précédentes, comprenant trois moteurs
d'aspiration (10), trois éléments de valve (23) et trois filtres (17).