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EP 0 697 188 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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31.10.2001 Bulletin 2001/44 |
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Date of filing: 13.07.1995 |
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International Patent Classification (IPC)7: A47L 15/42 |
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Device for controlling the flow of washing liquid for feeding the spraying rotors
of a dishwasher machine
Waschwasserzufuhrkontrolle für Sprüharme einer Geschirrspülmaschine
Dispositif pour le dosage contrôlé de liquide de lavage pour les bras d'arrosage d'une
machine à laver la vaisselle
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Designated Contracting States: |
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DE FR IT |
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Priority: |
27.07.1994 IT MI941602
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Date of publication of application: |
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21.02.1996 Bulletin 1996/08 |
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Proprietor: CANDY S.p.A. |
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I-20052 Monza (Milano) (IT) |
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Inventor: |
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- Fumagalli, Silvano
I-20052 Monza (IT)
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Representative: Mittler, Enrico et al |
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c/o Mittler & C. s.r.l.,
Viale Lombardia, 20 20131 Milano 20131 Milano (IT) |
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References cited: :
DE-A- 2 345 908 DE-A- 3 441 023 FR-A- 2 443 231 FR-A- 2 651 427
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DE-A- 3 406 698 DE-A- 3 911 305 FR-A- 2 457 670 US-A- 4 730 630
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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[0001] The present invention relates to a device for controlling the flow of washing liquid
for feeding the spraying rotors of a dishwasher machine.
[0002] Known dishwasher machines comprise a washing tub in which two horizontal shelves
are slidingly housed to hold the dishes to be washed, situated at the bottom (lower
shelf) and mid-height (upper shelf) respectively of the washing tub. Two spraying
rotors, lower and upper respectively, are associated to said shelves and fed with
the washing liquid (mixture of water and detergent) by a motor pump connected to a
sump located below the bottom of the washing tub and wherein the washing liquid diffused
by the spraying rotors is collected.
[0003] In most dishwashers the two rotors are fed simultaneously, assuming that both the
shelves have been loaded with dishes to be washed. The quantity of water which has
to be fed into the tub of the dishwasher has to be such that the pump does not go
into cavitation and that the pressure of the water emitted by the rotors is not too
low.
[0004] Nevertheless the growing interest in dishwashers which require smaller volumes of
water, with a consequent saving in detergent and electrical energy for heating the
washing liquid, is known. For this purpose devices for controlling the flow of liquid
sent by the pump to the rotors have been introduced and which allow one rotor to be
fed at a time alternately. In this way the volume of water required by the dishwasher
is smaller because the two rotors never operate simultaneously and the quantity of
liquid in circulation is smaller. These are substantially devices for diverting the
flow of washing liquid and are placed between the pump and the pipes for feeding liquid
to the rotors, inside of which a cut-off part moves alternatively between two working
positions, in each of which one of the pipes is closed while the other is open. The
movement of the cut-off part is achieved either by means of an actuator or under the
thrust of the liquid itself, the two working positions in this case being positions
of instable equilibrium.
[0005] Nevertheless these devices too, due to the fact that the washing liquid is any case
fed to both rotors, assume that both shelves are loaded with dishes to be washed.
This can be inconvenient in some dishwashers which have differentiated programmes
for washing twelve or six table settings. In this second case in fact it would be
more useful to load all the dishes on the upper shelf alone (both for reasons of convenience
for the user and better washing results, given that the temperature in the washing
tub is higher at the top than at the bottom), and to feed only the upper rotor.
[0006] EP-A-0 585 905 discloses a device according to the preamble of claim 1.
[0007] In view of the state of the art described here, the object of the present invention
is that of providing a device for controlling the flow of washing liquid for feeding
the spraying rotors which overcomes the aforementioned disadvantages.
[0008] In accordance with the present invention, this object is achieved thanks to a device
for controlling the flow of washing liquid for feeding a first spraying rotor and
a second spraying rotor of a dishwasher as set forth in claim 1.
[0009] The control device according to the present invention enables continuous or discontinuous
feeding of one of the two spraying rotors, while the other one can be independently
fed or not. The rotor associated to the outlet conduit controlled by said cut-off
means is preferably the lower one so that, should the dishwasher be programmed for
washing six table settings, the dishes can be loaded on only the upper shelf, and
the flow rate and pressure of the pump fully exploited to feed the washing liquid
to the upper rotor alone.
[0010] These and other features of the present invention will be made clearer by the following
detailed description of some of its embodiments, illustrated by way of a non-limiting
example in the accompanying drawings, in which:
Figure 1 is a section along a vertical plane of a dishwasher equipped with a control
device according to a first embodiment of the present invention;
Figure 2 is a section along line II-II of Figure 1;
Figure 3 is a section along line III-III of Figure 1;
Figure 4 is a section along a vertical plane of a dishwasher equipped with said control
device, during washing of a complete load of dishes;
Figure 5 is similar to Figure 1, but referred to the case of washing a partial load
of dishes;
Figure 6 is a similar section to that in Figure 1, showing a control device according
to a second embodiment of the present invention;
Figure 7 is a section along line VII-VII of Figure 6.
[0011] Figure 1 shows a washing tub 1 of a dishwasher, below which washing tub 1 a sump
2, wherein the washing liquid is collected, is mounted. Connected to the sump 2 is
a motor pump 3 which, taking the liquid from the sump 2, sends it to a lower spraying
rotor 4 extending from the bottom of the tub 1 inside the latter and related to a
lower loading shelf 100 and to an upper spraying rotor 4', positioned approximately
at mid-height inside the tub 1 and related to an upper loading shelf 101 (Figs. 4
and 5).
[0012] Connected to the outlet conduit 5 of the coil 6 of the pump 3 is a device 7 for cutting
off the flow of washing liquid, consisting of a chamber 8 wherein a diaphragm 9, moving
between two working conditions (shown as an unbroken line and dotted and dashed line
respectively in Figure 1), is hinged. Above the chamber 8 a substantially cylindrical
outlet conduit 10 is connected, divided internally into two semicylindrical conduits
11 and 12 by a baffle 13 (Fig. 2). Connected to the outlet conduit 10 is a flow diverter
14, also substantially cylindrical, and wherein a baffle 15, having a substantially
vertical lower section 18, is also provided and which divides internally the flow
diverter 14 into two semicylindrical conduits 16 and 17, and an upper elbow section
19 which joins the semicylindrical conduit 17 to a horizontal cylindrical conduit
20 for feeding the upper spraying rotor 4'. The flow diverter 14 is inserted in a
special hole 21 of the tub 1, and is attached by means of a ring nut 22. The lower
spraying rotor 4 is mounted, freely rotatably, above the flow diverter 14.
[0013] The diaphragm 9 has dimensions which correspond substantially to those of the chamber
8, and is attached at one end to a pin 24. Outside of the chamber 8 the pin 24 is
connected to an actuator 25 which causes displacement of the diaphragm 9 into the
two working positions. The diaphragm 9 has a semicircular opening 23 which, when the
diaphragm 9 is in the closure position shown by a dashed and dotted line in Figure
1, is positioned below the mouth of the semicylindrical conduit 12.
[0014] When the diaphragm 9 is in the opening position (shown by an unbroken line in Figure
1), both the semicylindrical conduits 11 and 12 are open, and the water coming from
the outlet conduit 5 of the pump 3 is distributed among the semicylindrical conduits
11, 16 and 12, 17, thus feeding simultaneously both the lower rotor 4 and the upper
rotor 4' (Fig. 4). When the diaphragm 9 is in the closure position, the mouth of the
semicylindrical conduit 11 is closed, while the mouth of the semicylindrical conduit
12 is open: thus feeding of the lower rotor 4 is interrupted, while the upper rotor
4' continues to be fed (Fig. 5).
[0015] Figures 6 and 7 show a second embodiment of the device according to the invention.
In this second embodiment, the control device forms a single body with the pump 3.
Directly connected to the outlet 5 of the pump 3 is the conduit 20, always open, for
feeding the upper rotor 4'. Said outlet conduit 5 comprises a substantially horizontal
cylindrical end section 26 flowing into a chamber 27 which extends above to form a
cylindrical appendage 28 whereon a conduit 29 is fitted and sealed for supporting
and feeding the lower rotor 4. This conduit 29 is mounted on the tub 1 in a similar
manner to the flow diverter 14 of the previous embodiment. Associated to the chamber
27 is a device for cutting off the fluid comprising a plug 30 controlled by an actuator
31 to move from a first working position, wherein the outlet of the end section 26
of the conduit 5 is open and leads into the chamber 27, to a second working position,
wherein the plug 30 closes the outlet of the end section 26 of the conduit 5 (position
shown by the dotted and dashed line in Figure 7).
[0016] When the plug 30 is in the opening position the water coming from the pump 3 is distributed
between the conduit 20, always open, for feeding the upper rotor 4' and the conduit
29 for feeding the lower rotor 4. When however the plug 30 is in the closure position,
the water cannot pass from the end section 26 of the outlet conduit 5 of the pump
3 into the chamber 27, and therefore the lower rotor 4 is not fed.
[0017] In Figure 7 a conduit 32 can also be seen, small in size and also connected to the
outlet conduit 5 of the pump 3. This conduit can be used for feeding pressurised liquid
in other points of the water supply circuit of the dishwasher. For example this pressurised
liquid can be used for cleaning the microfilter normally installed in the sump 2 to
filter the liquid coming from the washing tub 1. In dishwashers which allow recovery
of the washing liquid used during the final phase of rinsing of a washing cycle, the
conduit 32 can also be used for transferring the liquid contained in the washing tub
1 at the end of the final phase of rinsing to a recovery tank, wherein the liquid
is stored until the subsequent washing cycle. Thus the pump 3 performs a double function.
1. Device for controlling the flow of washing liquid for feeding a first spraying rotor
(4) and a second spraying rotor (4') of a dishwasher, comprising an inlet conduit
(5) connected to means for pumping the washing liquid, at least a first outlet conduit
(11;27,28) and a second outlet conduit (12;20) connected respectively to said first
and second spraying rotors (4,4'), and means (9;30) for controlling the flow of liquid
from said inlet conduit (5) to said outlet conduits (11;27,28;12;20), wherein said
means (9;30) comprises first means (9;30) associated to said first outlet conduit
(11;27;28) for controlling the opening and closure thereof and therefore selectively
cutting off the flow of liquid from the inlet conduit (5) to the first outlet conduit
(11;27,28), characterized in that the second outlet conduit (12;20;39) is left constantly open so that the second spraying
rotor (4') is always fed, during the washing cycle.
2. Control device according to claim 1, characterised in that said first outlet conduit and second outlet conduit are respectively a first semicylindrical
portion (11) and a second semicylindrical portion (12) of a cylindrical conduit (10)
defined by a baffle (13) inside said cylindrical conduit (10), said first cut-off
means comprising a diaphragm (9) which can be rotated between an opening position
and a closure position of said first semicylindrical portion (11) of the cylindrical
conduit (10).
3. Control device according to claim 1, characterised in that said first cut-off means comprise a plug (30) sliding between an opening position
and a closure position of said first outlet conduit (27,28).
4. Control device according to any one of the previous claims, characterised in that said first spraying rotor (4) is associated to a lower loading shelf (100), and said
second spraying rotor (4') is related to an upper Loading shelf (101).
5. Control device according to claim 4, characterised in that said first and second outlet conduits are two semicylindrical portions (38,39) of
a cylindrical conduit (34), said first and second cut-off means comprising respectively
a first and a second plug (42,43) sliding independently between a position of opening
and position of closure of a respective semicylindrical portion (38,39).
6. Control device according to any one of the previous claims, characterised in that said first spraying rotor (4) is associated to a lower loading shelf (100), and said
second spraying rotor (4') is related to an upper loading shelf (101).
1. Vorrichtung zum Steuern des Flusses einer Waschflüssigkeit zum Versorgen eines ersten
Sprührotors (4) und eines zweiten Sprührotors (4') einer Geschirrspülmaschine, mit
einer Einlaßdurchführung (5), die mit einer Einrichtung zum Pumpen der Waschflüssigkeit
verbunden ist, wenigstens einer ersten Auslaßdurchführung (11; 27, 28) und einer zweiten
Auslaßdurchführung (12; 20), die jeweils mit dem ersten und dem zweiten Sprührotor
(4, 4') verbunden sind, und einer Einrichtung (9; 30) zum Steuern des Flusses von
Flüssigkeit von der Einlaßdurchführung (5) zu den Auslaßdurchführungen (11; 27, 28;
12; 20), wobei die Einrichtung (9; 30) eine der ersten Auslaßdurchführung (11; 27,
28) zugeordnete erste Einrichtung (9; 30) zum Steuern ihres Öffnens und Schließens
und daher zum selektiven Sperren des Flusses von Flüssigkeit von der Einlaßdurchführung
(5) zur ersten Auslaßdurchführung (11; 27, 28) aufweist, dadurch gekennzeichnet, daß die zweite Auslaßdurchführung (12; 20; 39) konstant offen gelassen wird, so daß der
zweite Sprührotor (4') während des Waschzyklus immer versorgt wird.
2. Steuervorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß die erste Auslaßdurchführung und die zweite Auslaßdurchführung jeweils ein erster
semizylindrischer Teil (11) und ein zweiter semizylindrischer Teil (12) einer zylindrischen
Durchführung (10) sind, die durch eine Einbauplatte (13) innerhalb der zylindrischen
Durchführung (10) definiert sind, wobei die erste Sperreinrichtung eine Membran (9)
aufweist, die zwischen einer Öffnungsposition und einer Schließposition des ersten
semizylindrischen Teils (11) der zylindrischen Durchführung (10) gedreht werden kann.
3. Steuervorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß die erste Sperreinrichtung einen Stöpsel (30) aufweist, der zwischen einer Öffnungsposition
und einer Schließposition der ersten Auslaßdurchführung (27, 28) gleitet.
4. Steuervorrichtung nach einem der vorherigen Ansprüche, dadurch gekennzeichnet, daß der erste Sprührotor (4) zu einem unteren Beladeabteil (100) gehört und der zweite
Sprührotor (4') zu einem oberen Beladeabteil (101) gehört.
5. Steuervorrichtung nach Anspruch 4, dadurch gekennzeichnet, daß die erste und die zweite Auslaßdurchführung zwei semizylindrische Teile (38, 39)
einer zylindrischen Durchführung (34) sind, wobei die erste und die zweite Sperreinrichtung
jeweils einen ersten und einen zweiten Stöpsel (42, 43) aufweisen, die unabhängig
zwischen einer Öffnungsposition und einer Schließposition eines jeweiligen semizylindrischen
Teils (38, 39) gleiten.
6. Steuervorrichtung nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, daß der erste Sprührotor (4) zu einem unteren Beladeabteil (100) gehört und der zweite
Sprührotor (4') zu einem oberen Beladeabteil (101) gehört.
1. Dispositif pour la commande de l'écoulement de liquide de lavage pour l'alimentation
d'un premier rotor de pulvérisation (4) et d'un deuxième rotor de pulvérisation (4')
d'un lave-vaisselle, comportant une conduite d'entrée (5) reliée à des moyens de pompage
du liquide de lavage, au moins une première conduite de sortie (11; 27, 28) et une
deuxième conduite de sortie (12; 20) reliées respectivement aux dits premier et deuxième
rotors de pulvérisation (4, 4'), et des moyens (9; 30) destinés à commander l'écoulement
de liquide depuis ladite conduite d'entrée (5) vers lesdites conduites de sortie (11;
27, 28; 12; 20), dans lequel lesdits moyens (9; 30) comportent des premiers moyens
(9; 30) associés à ladite première conduite de sortie (11; 27, 28) afin de commander
l'ouverture et la fermeture de celle-ci et par conséquent couper de manière sélective
l'écoulement de liquide de la conduite d'entrée (5) vers la première conduite de sortie
(11; 27, 28), caractérisé en ce que la deuxième conduite de sortie (12; 20; 39) est laissée constamment ouverte de sorte
que le deuxième rotor de pulvérisation (4') est toujours alimenté, pendant le cycle
de lavage.
2. Dispositif de commande selon la revendication 1, caractérisé en ce que ladite première conduite de sortie et ladite deuxième conduite de sortie sont respectivement
une première partie semi-cylindrique (11) et une deuxième partie semi-cylindrique
(12) d'une conduite cylindrique (10) définie par une chicane (13) à l'intérieur de
ladite conduite cylindrique (10), lesdits premiers moyens de coupure comportant un
diaphragme (9) qui peut être entraîné en rotation entre une position d'ouverture et
une position de fermeture de ladite première partie semi-cylindrique (11) de la conduite
cylindrique (10).
3. Dispositif de commande selon la revendication 1, caractérisé en ce que lesdits premiers moyens de coupure comportent un bouchon (30) pouvant coulisser entre
une position d'ouverture et une position de fermeture de ladite première conduite
de sortie (27, 28).
4. Dispositif de commande selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit premier rotor de pulvérisation (4) est associé à un plateau de chargement inférieur
(100), et ledit deuxième rotor de pulvérisation (4') est lié à un plateau de chargement
supérieur (101).
5. Dispositif de commande selon la revendication 4, caractérisé en ce que lesdites première et deuxième conduites de sortie sont deux parties semi-cylindriques
(38, 39) d'une conduite cylindrique (34), lesdits premier et deuxième moyens de coupure
comportant respectivement un premier et un deuxième bouchon (42, 43) pouvant coulisser
indépendamment entre une position d'ouverture et une position de fermeture d'une partie
semi-cylindrique (38, 39) respective.
6. Dispositif de commande selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit premier rotor de pulvérisation (4) est associé à un plateau de chargement inférieur
(100), et ledit deuxième rotor de pulvérisation (4') est lié à un plateau de chargement
supérieur (101).