[0001] The present invention refers to a multi-dose dispenser of liquid additive products
for washing machines, in particular a dispenser of rinsing aid for dishwashing machines.
[0002] The need is largely known to exist in modern household dishwashing machines for a
multi-dose kind of dispenser to be provided, which is capable of delivering into the
washing vessel appropriately metered amounts of rinsing aid, which is usually in the
form of a viscous liquid with a high foaming capacity, during different phases of
a same operation cycle of the machine. For example, it is appropriate for a dose of
rinsing aid to be dispensed not only during a rinsing phase preceding the final drying
of the washload items, but also during the actual washing of the same washload items
in view of improving the soil removal effect.
[0003] To such a purpose, the dispenser shall not only have a sufficient holding capacity
to dispense an adequately high number of doses, but must also be capable of accurately
metering each single dose of liquid additive. Accordingly, the dispenser must include
a multi-dose reservoir for storing said adequate amount of liquid additive, as well
as means adapted to repeatedly measure and deliver the same additive in the form of
volumetrically metered amounts. The solution consisting in the rinsing aid being metered
through a time-controlled delivery is in fact quite out of the question, since the
density of the rinsing aid itself is strongly variable depending on the different
operating temperatures and the different kinds of additive used.
[0004] On the other hand, since the loading door of the dishwashing machine cannot be opened
during an operation cycle of the machine, such a volumetric metering cannot be accomplished
by having resort to a traditional "decanting" or pouring-off system, i.e. by making
use of a simple dispenser of the type that is mounted on the door of the machine and
is adapted to decant, i.e. pour into a volumetric metering chamber, each time that
the door of the machine is opened and closed again, a corresponding amount of rinsing
aid stored in a multi-dose reservoir.
[0005] In an effort to reconcile these contrasting needs, the proposal has been made of
providing the rinsing aid dispenser with a multi-dose rinsing-aid reservoir whose
bottom is in communication, via a filling aperture, with a volumetric metering chamber
situated therebelow, the bottom of which is in turn capable of communicating fluidly
with the washing vessel of a washing machine via a dispensing aperture. A moving double-shutter
member controlled by an electromagnet is adapted to be switched between a first and
a second position, in which it shuts the sole filling aperture and the sole dispensing
or delivery aperture, respectively.
[0006] In said first position, the liquid additive stored in the reservoir is allowed to
flow by gravity to fill said metering chamber, whereas in said second position the
amount of liquid additive contained in the metering chamber is allowed to be dispensed,
i.e. delivered into the washing vessel, by gravity.
[0007] This solution, although advantageously simple thanks to the use of a single actuator
member, has anyway a drawback in that, when said moving shutting member is being switched
over to said first and said second positions, both the filling aperture and the dispensing
aperture are temporarily open at the same time, actually, with the result that an
uncontrolled amount of liquid is able to flow out from the dispenser through said
two apertures arranged in series. This can alter to a substantial extent the actual
dose of additive being dispensed each time, especially in the case that the shutting
member is such as to switch over in a relatively slow manner.
[0008] DE 2239484 discloses a multiple-dose dispenser provided with three chambers and a plurality
of actuating elements, said elements actuating corresponding valves at the same time,
following the discharge of liquid from an intermediate chamber.
[0009] FR-A-2515220 discloses a multi-dose dispenser corresponding to the preamble of the independent
claim.
[0010] It therefore is a main purpose of the present invention to provide a multi-dose dispenser
of liquid additives for washing machines, which has a particularly simple and reliable
structure and is at the same time capable of ensuring a particularly accurate volumetric
metering of said additives without any need for a system of the afore mentioned "decanting"
kind to be implemented.
[0011] A further purpose of the present invention is to provide a multi-dose dispenser of
liquid additives of the above cited kind, which is capable of operating correctly
and in an accurate manner without any electrically energized actuating means being
actually required to ensure the operation of said dispenser.
[0012] According to the present invention, these and further aims are reached in a multi-dose
dispenser of liquid additives for washing machines incorporating the characteristics
as recited and defined in the appended independent claim 1. Preferred embodiments
of the invention are defined in the dependent claims.
[0013] Anyway, features and advantages of the present invention may be more readily understood
from the description that is given below by way of nonlimiting example with reference
to the accompanying drawings, in which:
- Figures 1 to 3 are schematic views of a first embodiment of the additive dispenser
according to the present invention, in respective operating positions thereof; and
- Figures 4 to 6 are schematic views of a second embodiment of the additive dispenser
according to the present invention, in respective operating positions thereof.
[0014] With reference to Figures 1 to 3 above, the additive dispenser can be contained within
a housing 1 which accommodates at least a reservoir 2 adapted to be filled, via an
appropriate upper aperture 3, with a substantial multi-dose amount of liquid additive,
such as for instance a rinsing aid for dishwashing machines.
[0015] The bottom of the reservoir 2 is capable of fluidly communicating, via a filling
aperture 4, with a volumetric metering chamber 5 situated therebelow, which in turn
comprises, in the bottom thereof, an aperture 6 for dispensing such an additive. The
latter can then be delivered into the washing vessel of the dishwashing machine via
an aperture 7 provided in the bottom of the housing 1.
[0016] The filling aperture 4 and the dispensing aperture 6 are associated to respective
shutter valves 8 and 9, respectively, which are distinct and capable of being actuated
in a differentiated manner, as this shall be described in a more detailed manner further
on.
[0017] The valve 8 is connected to a return spring 10 of the cap or similar type, or the
like, which normally keeps it at a distance from the aperture 4, which is therefore
open in the resting position thereof shown in Figure 1.
[0018] The valve 9 is in turn associated to a thrust spring 11, or the like, which normally
keeps it in a position in which it closes the aperture 6.
[0019] The valves 8, 9 are substantially juxtaposed, i.e. provided in a substantial side-by-side
arrangement, and are associated to an actuator 12, which may be of an electromagnetic
kind or - preferably - of a thermally actuated kind.
[0020] The actuator 12 comprises a moving member 13 adapted to act on the valves 8, 9 via
a lever 15 that is provided with respective pushing means 14, 16. In the resting position
illustrated in Figure 1, a return spring 17 keeps said pushing means 14, 16 of the
lever 15 in a condition in which they are substantially disengaged from the valves
8, 9.
[0021] As a result, in the resting position illustrated in Figure 1, the liquid stored in
the reservoir 1 is able to flow by gravity into the metering chamber 5, thereby filling
up the inner volume thereof.
[0022] When the actuator 12 is then operated, the moving member 13 thereof moves to act
on the lever 15, by overcoming the force of the return spring 17, to bring the pushing
means 14, 16 towards the respective valves 4, 6 until the dispenser, as ensured by
an appropriate sizing of the component parts thereof, is brought into the transient
condition illustrated in Figure 2. In this condition, the pushing means 14 brings
the valve 8 into closing the aperture 4, by overcoming the force of the return spring
10, whereas the valve 9 keeps being closed. In this manner, the occurrence of a transient
condition in which both apertures 4 and 6 are opened at the same time, under a resulting
uncontrolled leakage of liquid from the reservoir 2 via the chamber 5, is effectively
avoided.
[0023] It is just in the subsequent portion of the displacement travel of the lever 15 (Figure
3) that the pushing means 16 comes to engage the valve 9 to open the aperture 6, by
overcoming the force of the respective return spring 11. At this point, the volumetrically
metered amount of liquid that had previously filled up the chamber 5 flows out of
said chamber by gravity via the dispensing aperture 6.
[0024] In order to facilitate such a dispensing, said metering chamber 5 may be provided
with a vent pipe 18.
[0025] When the actuator 12 is deactivated, in a per se known manner, the return spring
17 causes the valve 9 to move back into the position in which it closes the dispensing
aperture 6 (Figure 2) and the return spring 10 then causes the valve 8 to move back
into its resting position in which it disengages from the aperture 4 (Figure 1). It
is just and solely at this point that the liquid stored in the reservoir 2 is able
to flow and fill by gravity the metering chamber 5, thereby preventing it from flowing
out through the aperture 6 as the valves 8, 9 are changing over.
[0026] In conclusion, such a differentiated actuation of the valves 8, 9 in the above described
manner is effective in avoiding any undesired delivery of additive during the changing-over
transients to open/close the apertures 4 and 6. This is particularly important in
the preferred case in which the actuator 12 is of the thermally operated kind, which
has on the one hand the advantage of not requiring any power-supply connection, but,
on the other hand, is only capable of ensuring relatively slow changing-over operations.
[0027] It shall be appreciated that the above described liquid-additive dispenser may be
the subject of a number of modifications without departing from the scope of the present
invention as set out in the claims.
[0028] For instance, according to the embodiment illustrated in Figures 4 to 6, the volumetric
metering chamber 5 may be provided in correspondence of a piston 19 that is capable
of sliding tightly with respect to a cylinder 20 arranged below the reservoir 2. In
particular, the metering chamber 5 is delimited within the cylinder 20 by two head-walls
21, 22 of the piston, each one of which preferably cooperates with the side surface
of the cylinder 20 through respective sealing rings 23, 24 or the like.
[0029] In the embodiment illustrated in Figures 4 to 6, the filling aperture 4 and the dispensing
aperture 6 are provided in correspondence of the side surface of the cylinder 20 and
the axial distance from each other is equal to or greater than the axial distance
of the two head-walls 21 and 22 of the piston from each other. The piston itself is
normally kept in its raised resting position shown in Figure 4, in which the metering
chamber 5 is in communication with the multi-dose reservoir 2 via the aperture 4 and,
therefore, is able to fill up with liquid additive, thanks also to the provision of
the vent tube 18.
[0030] The piston 19 is capable of being operated by the actuator 12 via a connection 25
provided with a return spring 17. When the actuator 12 is operated, the moving member
13 thereof acts on said connection 25 so as to cause the piston 19 to slide towards
a lower end-of-stroke, until the dispenser is brought into the transient condition
illustrated in Figure 5. In this condition, the walls 21 and 22 of the piston are
comprised between the apertures 4 and 6, which are therefore unable to communicate
with the metering chamber 5, with respect to which they are in fact closed. Also in
the case of the embodiment of the invention, therefore, the occurrence of a transient
condition in which both apertures 4 and 6 are opened at the same time, under a resulting
uncontrolled leakage of liquid from the reservoir 2 via the chamber 5, is effectively
avoided.
[0031] It is just in the subsequent portion of the displacement stroke of the piston 19
(Figure 6) that the aperture 6 is axially passed beyond and cleared by the wall 22,
thereby establishing a communication with the metering chamber 5. At this point, the
volumetrically metered amount of liquid that had previously filled up the chamber
5 flows out of said chamber by gravity via the dispensing aperture 6 itself.
[0032] When the actuator 12 is deactivated, the piston 19 slides back into its resting position
shown in Figure 4 by passing through the transient position shown in Figure 5.
[0033] Therefore, the apertures 4 and 6 are in the first place both in their closed condition
(Figure 5) and the aperture 4 is then cleared axially by the wall 21 of the piston
19 passing therebeyond, so that it is now able to communicate with the metering chamber
5. It is just and solely at this point that the liquid stored in the reservoir 2 is
able to flow by gravity to fill up the metering chamber 5, thereby preventing it from
flowing out through the aperture 6 as the walls 21 and 22 of the piston 19 are moving
during a change-over stroke thereof. In this case, it can be appreciated that said
piston walls are substantially equivalent to the valve members 8, 9 that have been
described previously with reference to Figures 1 to 3.
[0034] Also in the case of the embodiment illustrated in Figures 4 to 6, therefore, in which
the walls 21 and 22 of the piston are operated at the same time in the afore described
manner, this proves effective in avoiding any undesired delivery of additive during
the changing-over transients to open/close the apertures 4 and 6.
1. Multi-dose dispenser of liquid additive for washing machines, comprising at least
a multi-dose reservoir (2) for storing said liquid additives adapted to communicate
via a first normally open filling aperture (4) with a volumetric metering chamber
(5) which in turn comprises at least a normally closed dispensing aperture (6), shutter
means (8,9;21,22) being controlled by actuator means (10,11) to alternately open and
close said apertures in such a manner as to deliver through said second aperture pre-determined
amounts of additive that are let into the metering chamber through said first aperture,
characterized in that said shutter means (8, 9; 21, 22) comprises a distinct valve member for each one
of said apertures (4,6), the shutter means operating in such a manner to only open
the second aperture (6) after the first aperture (4) has been closed, and to open
again the first apertures (4) only after the second aperture (6) has been closed,
said valve members (8,9) being adapted to be operated in a differentiated manner by
a thermal actuator means (12) via transmission means (14,16), said transmission means
comprising a lever (15) connected to said thermal actuator means (12) and said valve
members (8, 9), said valves members being provided in a substantially side-by-side
arrangement.
2. Liquid-additive dispenser according to claim 1, characterized in that said thermal actuator means comprise a thermally actuated member (12) adapted, to
change over said shutter means (8, 9; 21, 22) between respective positions for closing
and opening said apertures (4, 6).
3. Liquid-additive dispenser according to claim 1, characterized in that said volumetric metering chamber (5) is provided in correspondence of a piston (19)
adapted to slide tightly, as controlled by said actuator means (12), with respect
to a cylinder (20) arranged below said reservoir (2), the metering chamber (5) being
delimited, within the cylinder (20), by two walls (21, 22) of the same piston.
4. Liquid-additive dispenser according to claim 3, characterised in that said apertures (4, 6) are provided in correspondence of the side surface of the cylinder
(20) and the axial distance from each other is equal to or greater than the axial
distance of said walls (21, 22) of the piston (19) from each other.
1. Mehrfachdosierungs-Ausgabevorrichtung für flüssige Zusatzmittel für Waschmaschinen,
die mindestens ein Mehrfachdosierungsfach (2) zur Aufnahme des flüssigen Zusatzmittels
umfasst, das geeignet ist, über eine erste, normalerweise offene Einfüllöffnung (4)
mit einer Volumendosierungskammer (5) zu kommunizieren, die ihrerseits mindestens
eine normalerweise geschlossene Ausgabeöffnung (6) aufweist, ferner Klappenmittel
(8, 9; 21, 22), die von Betätigungsmitteln (10, 11) gesteuert werden, um die Öffnungen
abwechselnd zu öffnen und zu schließen, so dass durch die zweite Öffnung vorbestimmte
Mengen von Zusatzmitteln geliefert werden, die durch die erste Öffnung in die Dosierungskammer
eingelassen werden, dadurch gekennzeichnet, dass die Klappenmittel (8, 9; 21, 22) für jede Öffnung (4, 6) ein spezifisches Ventilmittel
umfassen und dass die Klappenmittel so funktionieren, dass sie die zweite Öffnung
(6) erst dann öffnen, nachdem die erste Öffnung (4) geschlossen worden ist, und die
erste Öffnung (4) erst dann wieder öffnen, nachdem die zweite Öffnung (6) geschlossen
worden ist, wobei das Ventilmittel (8, 9) geeignet ist, auf differenzierte Weise von
einem thermischen Betätigungsmittel (12) über ein Übertragungsmittel (14, 16) betrieben
zu werden, wobei das Obertragungsmittel einen Hebel (15) aufweist, der mit dem thermischen
Betätigungsmittel (12) und den Ventilmitteln (8, 9) verbunden ist, wobei die Ventilmittel
in einer im wesentlichen seitlich benachbarten Anordnung angeordnet sind.
2. Ausgabevorrichtung für flüssige Zusatzmittel gemäß Anspruch 1, dadurch gekennzeichnet, dass das thermische Betätigungsmittel ein thermisch betätigtes Element (12) umfasst, das
geeignet ist, die Klappenmittel (8, 9; 21, 22) zwischen den jeweiligen Stellungen
zum Schließen und Öffnen der Öffnungen (4, 6) hin und her zu schalten.
3. Ausgabevorrichtung für flüssige Zusatzmittel gemäß Anspruch 1, dadurch gekennzeichnet, dass die Volumendosierungskammer (5) in Verbindung mit einem Kolben (19) vorgesehen ist,
der sich unter der Steuerung des Betätigungsmittels (12) nahe an einem Zylinder (20)
entlang bewegt, der unter dem Fach (2) angeordnet ist, wobei die Dosierungskammer
(5) innerhalb des Zylinders (20) von zwei Wänden (21, 22) des Kolbens begrenzt wird.
4. Ausgabevorrichtung für flüssige Zusatzmittel gemäß Anspruch 3, dadurch gekennzeichnet, dass die Öffnungen (4, 6) in Entsprechung zur Seitenfläche des Zylinders (20) vorgesehen
sind und die Axialdistanz voneinander größer oder gleich der Axialdistanz der Wände
(21, 22) des Kolbens (19) voneinander ist.
1. Distributeur multidose d'additif liquide pour machines à laver, comportant au moins
un réservoir multidose (2) destiné à contenir ledit additif liquide adapté pour communiquer,
par une première ouverture de remplissage normalement ouverte (4), avec une chambre
de dosage volumétrique (5) qui comporte à son tour au moins une ouverture de distribution
normalement fermée (6), des moyens obturateurs (8, 9 ; 21, 22) étant commandés par
des moyens actionneurs (10, 11) pour ouvrir et fermer alternativement lesdites ouvertures
de manière à délivrer, à travers ladite seconde ouverture, des quantités prédéterminées
d'additif qui sont introduites dans la chambre de dosage à travers ladite première
ouverture, caractérisé en ce que lesdits moyens obturateurs (8, 9 ; 21, 22) comportent un élément de soupape distinct
pour chacune desdites ouvertures (4, 6), les moyens obturateurs fonctionnant de manière
à ouvrir uniquement la seconde ouverture (6) après que la première ouverture (4) ait
été fermée, et pour rouvrir la première ouverture (4) uniquement après que la seconde
ouverture (6) ait été fermée, lesdits éléments de soupape (8, 9) étant adaptés pour
être actionnés de manière différenciée par un moyen actionneur thermique (12) par
l'intermédiaire de moyens de transmission (14, 16), lesdits moyens de transmission
comportant un levier (15) relié audit moyen actionneur thermique (12) et auxdits éléments
de soupape (8, 9), lesdits éléments de soupape étant disposés selon un agencement
sensiblement côte à côte.
2. Distributeur d'additif liquide selon la revendication 1, caractérisé en ce que ledit moyen actionneur thermique comporte un élément actionné thermiquement (12)
adapté pour faire basculer lesdits moyens obturateurs (8, 9 ; 21, 22) entre des positions
respectives destinées à fermer et ouvrir lesdites ouvertures (4, 6).
3. Distributeur d'additif liquide selon la revendication 1, caractérisé en ce que ladite chambre de dosage volumétrique (5) est agencée en correspondance avec un piston
(19) adapté pour coulisser de manière étanche, lorsqu'il est commandé par ledit moyen
actionneur (12), par rapport à un cylindre (20) agencé sous ledit réservoir (2), la
chambre de dosage (5) étant délimitée, à l'intérieur du cylindre (20), par deux parois
(21, 22) du même piston.
4. Distributeur d'additif liquide selon la revendication 3, caractérisé en ce que lesdites ouvertures (4, 6) sont agencées en correspondance avec la surface latérale
du cylindre (20) et la distance axiale de l'une à l'autre est supérieure ou égale
à la distance axiale de l'une à l'autre desdites parois (21, 22) du piston (19).