[0001] The present invention relates to a dishwasher of the type comprising a washing container
for accommodating the dishes to be washed, a spraying device for spraying a washing
liquid onto the dishes arranged in the washing container, and a detergent container
for dispensing detergent during the wash cycle of the dishes.
[0002] Dishwashers are known with a detergent container, formed in the door of the dishwasher,
which can be opened and closed by a cover. Before every use of the dishwasher, the
user loads a dose of detergent into the detergent container (the volume of which is
dimensioned to contain only one dose of detergent) and manually closes the cover,
which remains closed by virtue of a snap-lock system. After switching on the dishwasher
and closing the door, a wash cycle starts during which an actuator disengages the
restraining system of the cover. In this manner, the entire content of the detergent
container is poured into the washing container, in which it mixes with the water which
is recirculated and sprayed onto the dishes.
[0003] With the dishwashers of the prior art, the user must load the detergent before each
wash cycle and manual dosing a very small amount of powder or liquid, as precisely
as possible, which activity is perceived as intrinsically annoying and sometimes difficult,
in particular for elderly people. Furthermore, the fact that the dishwasher detergent
must be stored out of the reach of children, and therefore is often placed in very
high cabinets, which can be reached only by climbing onto a chair or onto a ladder,
must also be taken into account.
[0004] It is thus the object of the invention to facilitate the loading and dosing of detergent
in dishwashers.
[0005] These and other objects are achieved by means of a dishwasher according to claim
1. Some advantageous embodiments are the object of the dependent claims.
[0006] According to an aspect of the invention, a dishwasher comprises:
- a washing container for accommodating dishes to be washed,
- a spraying device for spraying a washing liquid onto the dishes in the washing container,
- a detergent container forming an inner space for containing a detergent, a dispensing
opening for dispensing the detergent from the inner space towards the washing container,
and a shutter member for opening and closing the dispensing opening,
- an electronic control device which controls the activation of the spraying device
and of a dispensing actuator acting on the shutter member,
wherein:
- the inner space of the detergent container is adapted to accommodate a total volume
of detergent sufficient for a plurality of wash cycles,
- the dishwasher further comprises a dosing device in communication with the dispensing
opening and which can be activated by means of the dispensing actuator for dosing
and dispensing, during a single wash cycle, a partial volume of detergent provided
for said single wash cycle.
[0007] By virtue of the sizing of the detergent container and of the dosing device and in
that the dispensing actuator also actuates the dosing device, the detergent container
can be filled less frequently, e.g. once a week or a month, with a large amount of
detergent, without the user being burdened by the need to accurately dose at all,
and the dishwasher can be used for a given period of time and for a given number of
washes without needing to refill or dose the detergent.
[0008] Furthermore, by virtue of the dosing device actuated automatically during the wash
cycle, the user only needs to load the detergent, but no longer dose it for the single
wash cycle.
[0009] In order to better understand the invention and appreciate its advantages, some non-limiting
embodiments will be described below by way of example with reference to the figures,
in which:
- figure 1 is a diagrammatic front view of a dishwasher according to an embodiment of
the invention;
- figure 2 is a diagrammatic section view of a detergent container and of a dosing device
of the dishwasher according to an embodiment, in a first configuration of use (dispensing
opening closed and dosing compartment empty);
- figure 3 shows the detergent container and the dosing device in figure 2 in a second
configuration of use (dispensing opening open and dosing compartment filled);
- figure 4 shows the detergent container and the dosing device in figure 2 in a third
configuration of use (dispensing opening closed again and dosing compartment still
filled but in dosed detergent dispensing step);
- figures 5 and 6 are two section views of a detergent container for the dishwasher
according to an embodiment;
- figure 7 is a diagrammatic side view of a dishwasher according to a further embodiment
of the invention;
- figure 8 is a front view of a rinse-aid and detergent dispensing assembly of the dishwasher
according to an embodiment;
- figure 9 diagrammatically shows part of a hydraulic circuit of the dishwasher according
to an embodiment;
- figure 10 is a partial section view of the detergent container and of the dosing device
of the dishwasher according to a further embodiment.
[0010] With reference to the figures, a dishwasher 1 comprises a washing container 2 adapted
to accommodate dishes 3 to be washed and which can be closed by a door 4.
[0011] At least one spraying device is positioned inside the dishwasher 1, e.g. a spraying
arm 5 rotatably mounted in the washing container 2 and forming a plurality of spraying
nozzles 6 for spraying a washing liquid onto the dishes 3 accommodated in the washing
container 2. A pump 7 is hydraulically connected, e.g. by means of a delivery pipe
8, to the spraying arm 5 for feeding the washing liquid to the spraying nozzles 6.
[0012] The dishwasher 1 also comprises a heating device 9, adapted to heat the washing liquid,
e.g. an electric resistor arranged in a collection tank 10 of the washing liquid.
The collection tank 10, preferably formed in a lower zone of the washing container
2 or under the washing container 2, is connected to the pump 7 to allow the drawing
of the either cold or heated washing liquid needed for washing the dishes 3. The collection
tank 10 and/or the pump 7 are further connected to an inlet valve 11 for loading network
water, and to a discharge duct 12 for discharging the washing liquid. The inlet valve
11 is placed in a supply conduit 36 which can be connected to the water network and
which forms an air break 37 to prevent drawing back of liquid into the water network
and passes through a water softener device 38 (decalcifier) before opening into the
washing container, in particular into the collection tank 10.
[0013] Dishwasher 1 further comprises a detergent container 14 forming an inner space 15
for containing a detergent 16 (powder or liquid), a dispensing opening 17 for dispensing
detergent 16 from the inner space 15 towards the washing container 2, and a shutter
member 18 for opening and closing the dispensing opening 17.
[0014] A control device, e.g. an electronic control board 13, is configured to allow the
selection of a dish treatment program from a plurality of treatments programs, and
controls the actuation of the pump 7, of the heating device 9, of the inlet valve
11 and of a dispensing actuator 20 acting on the shutter member 18.
[0015] According to an aspect of the invention, the inner space 15 of the detergent container
14 is sized to accommodate a total volume of detergent sufficient for a plurality
of wash cycles, and the dishwasher 1 further comprises a dosing device 19 in communication
with the dispensing opening 17 and which can be activated by means of the dispensing
actuator 20 for dosing and dispensing, during a single wash cycle, a partial volume
of detergent 16 for said single wash cycle.
[0016] By virtue of the sizing of the detergent container 14 and of the dosing device 19
and to the fact that the dispensing actuator 20 also actuates the dosing device 19,
it is possible to:
- fill the detergent container less frequently, e.g. once a week or once a month,
- fill the detergent container with a large amount of detergent without the user being
burdened with accurate dosing at all, and
- use the dishwasher 1 for a period of time and a number of washes without needing to
refill or dose the detergent every time.
[0017] Furthermore, by virtue of the fact that the dosing device 19 is actuated automatically
during the wash cycle, the user only needs to load the detergent, but no longer dose
it for the single wash cycle.
[0018] According to an embodiment, the detergent container 14 can be either extracted or
removed from the dishwasher 1 to facilitate its filling. Advantageously, the dishwasher
1 forms a coupling seat 21 for a removable mechanical connection, e.g. snap-locking
or bayonet, of the detergent container 14 and for a connection of the dispensing opening
17 into communication with a dispensing conduit 22 communicating with the inside of
the washing container 2.
[0019] The coupling seat 21 may be formed in a side wall 23 of the washing container 2,
e.g. in the inner surface of the door 4 (
figure 7).
[0020] According to an embodiment, the detergent container 14 forms a loading opening 23
(in addition to the dispensing opening 17) for pouring detergent 16 into the inner
space 15 of the detergent container 14.
[0021] The loading opening 23 is preferably larger than the dispensing opening 17 to facilitate
and speed up the filling of the detergent container 14 and to facilitate an airtight
seal of the smaller dispensing opening 17 by means of the shutter member 18.
[0022] The loading opening 23 can be opened and closed by a cover 24 (possibly provided
with a seal) which can be directly and permanently connected (e.g. hinged or inserted
in the form of a gate valve) to the detergent container 14 (so that it cannot be lost
but can easily be washable and repairable). Alternatively, the cover 24 may be provided
as fully detachable component and therefore more easily replaceable.
[0023] According to an embodiment, the cover 24 may be formed or connected to the coupling
housing 21 so as to close the loading opening 23 when the detergent container 14 is
coupled to the coupling seat 21 so as to free the loading opening 23 when the detergent
container 14 is detached from the coupling housing 21. This reduces the number of
components and the number of operations required for loading the detergent.
[0024] In an embodiment (
figure 2), with the detergent container 14 in position of use, the dispensing opening 17 is
formed on a lower side of the detergent container 14, so as to facilitate the dispensing
of the detergent 16 by virtue of the force of gravity. The loading opening 23 may
be formed on an upper side of the detergent container 14, opposite to the dispensing
opening 17, to facilitate the connection and the movement of the loading cover 24
and of the shutter member 18 without mutual encroachments.
[0025] According to a further embodiment, the dispensing opening 17 may be formed in the
loading cover 24 with the advantage of being able to make the base body of the detergent
container 14 with a single opening.
[0026] According to an embodiment
(figures 2,
3, 4) the shutter member 18 may comprise:
- a translatable shutter, e.g. gate valve or a piston, or
- a rotating shutter, e.g. a ball, a cylinder, a plate, or
- an elastically deformable shutter, e.g. a membrane.
[0027] The shutter member 18 can be coupled to the dispensing opening 17 and can be displaced
with respect to the dispensing opening by means of the flow actuator 20 to allow and
prevent the release of detergent 16 from the dispensing opening 17 in controlled manner.
[0028] The shutter member 18 may be permanently and elastically urged into a closed position
(e.g. by means of a spring 35,
figure 5) to ensure the airtight seal of the dispensing opening 17 when the detergent container
14 is detached from the dishwasher and/or when the dispensing actuator 20 is deactivated.
[0029] Alternatively, the shutter member 18 may be shaped and displacable so as to always
block the passage of detergent when the shutter member 18 stops immobile in any one
position, and so as to allow the passage of detergent or even convey the detergent,
when the shutter member 18 is moved with respect to the dispensing opening 17.
[0030] Examples of this latter embodiment are ball or piston or box shutters having one
or more cavities adapted to receive a limited quantity of detergent when they are
facing and communicating with the dispensing opening 17 and to release this limited
amount of detergent when they are displaced out of communication with the dispensing
opening 17.
[0031] According to an embodiment, the dosing device 19 delimits a dosing space 25 which
is much smaller than the inner space of the detergent container 14, and which can
be switched (displaced or connected) by means of the dispensing actuator 20:
- into communication with the dispensing opening 17 to fill with a dosed quantity of
detergent 16 and
- successively, into communication with a dispensing conduit 22 and/or with the feeding
conduit 36 of the network water, or directly with the inside of the washing container
2 to release the dosed quantity of detergent 16 into the washing container 2.
[0032] According to an embodiment, the dosing space 25 may be formed in a dosing container
26 which is either distinct or separate from the shutter 20 and possibly installed
permanently in the dishwasher 1. This makes it possible to make the dosing container
25 independently from the detergent container 14 and to couple it easily and permanently
with the dispensing actuator 20 (without needing to make a detachable coupling) in
addition to not exposing the dosage compartment 26 to handling and to the consequent
risk of displacement or damage, by the user.
[0033] According to an alternative embodiment, the dosing space 25 may be formed directly
in the shutter member 18, thus reducing the number of individual components to be
made and to move, at the cost of greater complexity of the shape of the shutter member
18.
[0034] According to an embodiment, the dosing space 25 can be switched (displaced or connected)
by means of the dispensing actuator 20 into communication with the water feed conduit
36 or with the pump 7 to completely empty the dosed detergent 16, to wash the dosing
space 25 and to achieve an intense mixing of the detergent 16 with the washing liquid
(
figure 9).
[0035] According to an embodiment, the volume of the dosing space 25 may be adjustable to
adapt the dosed amount of detergent 16 to the wash cycle conditions, to the user's
preferences or to the type of detergent used.
[0036] According to an embodiment (
figure 10), the volume of the dosing space 25 can be adjusted by either displacing or deforming
at least one wall 27 delimiting the dosing space 25, e.g. by means of the same dispensing
actuator 20.
[0037] Either additionally or alternatively, the partial volume of detergent 16 for the
single wash cycle is adjustable, preferably in automatic manner, e.g. by adjusting
the number of actuations of the dosing device 19 and/or by adjusting the volume of
the dosing space 25 and/or by adjusting the number of switches of the dosing space
25 into communication with the dispensing opening 17 and with the dispensing conduit
22.
[0038] The dispensing actuator 20 may comprise a single actuator controlled by the control
unit 13, which moves the shutter member 18, switches the dosing space 25 and, if provided,
adjusts the volume of the dosing space 25, e.g. a linear actuator (linear motor, solenoid),
rotary actuator (electric motor) or roto-translating actuator (linear electric motor
and rotary switch assembly).
[0039] Figure 10 shows an example of a linear and rotary flow actuator 20 which displaces the shutter
member 18 and the dosing container 26 by means of the linear motion and displaces
the wall 27 of the dosing container 26 by means of the rotational movement and a worm
screw mechanism 28 to adjust the volume of the dosing space 25.
[0040] Alternatively, the dispensing actuator 20 may comprise a plurality of single actuators
controlled by the control unit 13, which move the shutter member 18, switch the dosing
space 25 and, if provided, adjust the volume of the dosing space 25, e.g. one or more
linear, rotary or roto-translating actuators.
[0041] According to an embodiment, the dosing device 19 may be permanently fixed to the
detergent container 14 and detached together with it from the dishwasher 1. Alternatively,
the dosing device 19 can be permanently fixed in the dishwasher 1.
[0042] In order to avoid the risk of deterioration of the detergent 16 inside the detergent
container 14, due to a prolonged and repeated exposure to high operating temperatures
of the dishwasher 1, a layer of temperature-insulating material 29, for example a
single or multiple air gap or foam material is advantageously provided between the
inner space 15 of the detergent container 14 and the inner space of the washing container
2 and/or a cooling system 30, e.g. a cool water conduction system, in heat exchange
relationship with the inner space 15 of the detergent container 14 (
figure 7).
[0043] According to an embodiment, the dishwasher 1 comprises a system 31 for detecting
the quantity of dishes 3 and/or of the dirt intensity of the dishes 3 arranged in
the washing container 2, and the control circuit 13 adjusts the partial volume of
detergent 16 for the single wash cycle according to the quantity of dishes 3 and/or
the dirt intensity detected.
[0044] The detecting system 31 may comprise a temperature sensor 32 of the washing liquid,
connected to the control circuit 13, which control circuit 13 calculates a temperature
gradient during the heating of the washing liquid, said temperature gradient being
indicative of the mass and thermal capacity of the dishes 3.
[0045] Either additionally or alternatively, the detection system 31 may comprise a washing
liquid turbidity sensor 33 (e.g. optical), connected to the control circuit 13, said
detected turbidity being indicative of dirt of the dishes 3. The turbidity sensor
33 and/or the temperature sensor 32 may be positioned in the collection tank 10.
[0046] Furthermore, it is noted that the detergent container 14 and the dosing device 19
are provided in addition to, and preferably distanced from, a rinse-aid container
and doser 34.
[0047] Figures from 2 to 6 show the function of dispensing and dosing of the detergent 16. With the detergent
container 14 engaged with the coupling seat 21, the shutter member 18 is engaged by
a coupling portion 40 of the dosing container 26 so as to be displacable together
between:
- a first position (figures 2, 4), in which the dispensing opening 17 is closed by means of the shutter member 18
and the dosing space 25 is in communication with the dispensing conduit 22 or directly
with the washing tank 2,
- a second position (figure 3), in which the dispensing opening 17 is open and the dosing space 25 is in communication
with the dispensing conduit 17.
[0048] By displacing the shutter 18 and the dosing container 26 from the first position
to the second position
(figure 3), the dosing space 25 fills with detergent 16. Successively, by displacing the shutter
18 and the dosing container 26 from the second position back to the first position
(figure 4), the dispensing opening 22 is closed again and the dosing space 25 releases the
volume of detergent 16 precisely dosed.
[0049] Advantageously, the used detergent is a liquid detergent, a powder detergent or a
granular detergent.
[0050] Obviously, a person skilled in art may make further changes and variants to the dishwasher
1 and detergent container 14 described hereto without departing from the scope of
protection of the invention, as defined in the following claims.
1. A dishwasher (1), comprising:
- a washing container (2) for accommodating dishes (3) to be washed,
- a spraying device (5, 6, 7) for spraying a washing liquid onto the dishes (3) in
the washing container (2),
- a detergent container (14) forming an inner space (15) for containing a detergent
(16), a dispensing opening (17) for dispensing the detergent (16) from the inner space
(15) towards the washing container (2), and a shutter member (18) for opening and
closing the dispensing opening (17),
- an electronic control device (13) which controls the activation of the spraying
device (5, 6, 7) and of a dispensing actuator (20) acting on the shutter member (18),
characterized in that:
- the inner space (15) of the detergent container (14) is adapted for accommodating
a total volume of detergent (16) sufficient for a plurality of wash cycles,
- the dishwasher (1) further comprises a dosing device (19) in communication with
the dispensing opening (17) and which can be activated by means of the dispensing
actuator (20) for dosing and dispensing, during a single wash cycle, a partial volume
of detergent provided for said single wash cycle.
2. A dishwasher (1) according to claim 1, wherein the detergent container (14) can be
extracted from the dishwasher (1).
3. A dishwasher (1) according to claim 1 or 2, wherein the detergent container (14) forms
a loading opening (23) for pouring the detergent (16) in the inner space (15) of the
detergent container (14), wherein the loading opening (23) is larger than the dispensing
opening (17) and can be opened and closed by means of a cover (24).
4. A dishwasher (1) according to one of the preceding claims, wherein the shutter member
(18) is selected in the group consisting of:
- a translatable shutter,
- a gate valve,
- a piston,
- a rotating shutter,
- a ball,
- a cylinder,
- a plate,
- an elastically deformable shutter,
- a membrane.
5. A dishwasher (1) according to one of the preceding claims, wherein the shutter member
(18) is permanently elastically urged in a closed position to ensure the airtight
seal of the dispensing opening (17) when the detergent container (14) is detached
from the dishwasher and when the dispensing actuator (20) is deactivated.
6. A dishwasher (1) according to one of the preceding claims, wherein the shutter member
(18) is shaped and movable so as to:
- always block the passage of detergent when the shutter member (18) is stationary
in any one position, and
- allow the passage of detergent when the shutter member (18) is moved with respect
to the dispensing opening (17).
7. A dishwasher (1) according to one of the preceding claims, wherein the dosing device
(19) delimits a dosing space (25) which is smaller than the inner space (15) of the
detergent container (14),
said dosing space (25) being switchable by means of the dispensing actuator (20):
- in communication with the dispensing opening (17) to fill the dosing space (25)
by means of a dosed quantity of detergent (16) and
- in communication with a dispensing conduit (22) to release the dosed quantity of
detergent (16) into the washing container (2).
8. A dishwasher (1) according to claim 7, wherein the dosing space (25) is formed in
a dosing container (26) which is separate from the shutter (20) and installed permanently
in the dishwasher (1), or
wherein the dosing space (25) is directly formed in the shutter member (18).
9. A dishwasher (1) according to one of claims 7 to 8, wherein the dosing space (25)
is switchable by means of the dispensing actuator (20) in communication with a water
conduit (36) to completely empty the dosed detergent (16) and to wash the dosing space
(25).
10. A dishwasher (1) according to one of the preceding claims, wherein the partial volume
of detergent (16) for the single wash cycle is adjustable in an automatic manner.
11. A dishwasher (1) according to claim 10, comprising a system for detecting the quantity
of dishes (3) arranged in the washing container (2), and the control device (13) adjusts
the partial volume of detergent (16) for the single wash cycle according to the quantity
of dishes (3) detected.
12. A dishwasher (1) according to claim 11, wherein the system for detecting the quantity
of dishes (3) comprises a temperature sensor (32) of the washing liquid connected
with the control device (13), wherein the control circuit (13) calculates a temperature
gradient during the heating of the washing liquid, said temperature gradient being
indicative of the quantity of dishes (3).
13. A dishwasher (1) according to one of claims 10 to 12, comprising a system for detecting
the dirt intensity of the dishes (3) arranged in the washing container (2), and the
control device (13) adjusts the partial volume of detergent (16) for the single wash
cycle according to the detected dirt intensity.
14. A dishwasher (1) according to claim 13, wherein the system for detecting the dirt
intensity comprises a turbidity sensor (33) of the washing liquid, connected with
the control device (13), said turbidity detected being indicative of the dirt of the
dishes (3).
15. A dishwasher (1) according to one of the preceding claims, comprising:
- a temperature-insulating layer (29) between the inner space (15) of the detergent
container (14) and an inner space of the washing container (2), and/or
- a cooling system (30) in heat exchange relation with the inner space (15) of the
detergent container (14), and/or
said detergent container (14) and the dosing device (19) are provided in addition
to a container and dosing device for the rinse-aid (34).