[0001] This invention relates to a washing appliance, in particular a washing appliance
equipped with a detergent detection system.
[0002] Washing appliances comprise electrical appliances such as, for example:
- washing machines for cleaning clothes, bed sheets, etc.;
- dishwashers for washing dishes, cutlery, pans, etc.
[0003] In particular, washing appliances called "laundry washers" are suitable for carrying
out at least a washing treatment on textile articles made of any fibre or in any colour
and include machines known as "washing machines" and machines known as "washer dryers",
if in addition to washing they also carry out at least a treatment for drying textile
articles.
[0004] In this text, the term "washing cycle" means the steps making up the washing treatment
in their entirety, that is to say, pre-wash, if any, washing proper (main wash) and
rinsing, if any.
[0005] Also, the term "washing agent" in this text means both detergents and washing aids
such as bleach, descaling agent, fabric softener and rinse aid.
[0006] There are laundry washers comprising a washing agent feed line and a washing tank
with a drum in which the laundry to be washed is placed. The washing agent feed line
leads into the washing tank and includes a drawer which can be pulled out at least
partly and which usually comprises four compartments into which the user can put washing
agents (detergents and washing aids such as, for example, fabric softener, bleach,
etc.) to be used during the washing cycle: a first compartment for pre-wash detergent,
a second compartment for main wash detergent, a third compartment for bleach and a
fourth compartment for fabric softener.
[0007] Washing appliances of the kind described above are not free of disadvantages, however.
[0008] The washing cycle performed by the machine is totally independent of the washing
agents placed in the washer drawer. In prior art laundry washers, it is not possible
for the user to tell the machine what type of washing agents have been placed in the
drawer.
[0009] The Applicant has, however, found that, in order to optimize their action, some of
the washing agents, in particular some of the washing aids, should be fed into the
washing tank at a specific step in the washing cycle. This is particularly true of
bleach. In fact, traditional bleach should be fed into the washing tank during the
main wash step, while non-chlorine bleach, suitable for coloured, synthetic and wool
fibres should be used during the rinse step or, alternatively, during a specific,
especially designed pre-wash.
[0010] This invention has for an aim to overcome the above mentioned disadvantages by providing
a washing appliance which enables the effect of the washing agents to be optimized.
[0011] Another aim of the invention is to provide a washing appliance that can prevent errors
caused by the user placing a washing agent in the wrong compartment.
[0012] These aims and others, which are more apparent in the description which follows,
are achieved, in accordance with this invention, by a washing appliance having the
structural and functional characteristics described in the independent claims herein.
Alternative embodiments of the appliance are described in the dependent claims.
[0013] The invention will now be described in more detail with reference to the accompanying
drawings, which illustrate a non-limiting preferred embodiment of it.
- Figure 1 is a partial view of a washing appliance according to this invention;
- Figure 2 is a schematic view of a washing appliance according to this invention.
[0014] With reference to the accompanying drawings, the numeral 1 denotes a washing appliance
according to this invention.
[0015] The washing appliance 1 is designed preferably for household use and comprises a
washing tank 2 suitable for containing the washing liquid used for a washing treatment.
Said washing liquid is advantageously comprised of a mixture of water and a washing
agent. Inside the washing tank 2, the washing appliance 1 comprises means for containing
the articles to be washed, said containing means defining at least a space for accommodating
the articles to be washed. In the case of a laundry washer, for example, the containing
means comprise a rotary drum in which the laundry to be washed is placed. Similarly,
in the case of a dishwasher, the containing means comprise one or more racks which
can usually be pulled out by means of suitable carriages.
[0016] The washing appliance 1 also comprises a feed line 3 for feeding at least one washing
agent. The feed line 3 leads into the washing tank 2 and includes at least one compartment
30 accessible by the user who puts the washing agent into it. As stated above, washing
agent means detergents and/or washing aids.
[0017] The washing appliance 1 may be one of several different kinds of machine but in the
preferred embodiment it is a laundry washer or a dishwasher.
[0018] The washing appliance 1 also comprises at least one sensor 4 for detecting predetermined
chemical and/or physical properties of the at least one washing agent. The sensor
4 is located upstream of the washing tank 2 relative to the direction in which the
washing agent flows along the feed line 3. The flow of the washing agent along the
feed line 3 starts at the at least one compartment 30 and ends at the washing tank
2.
[0019] Preferably, the sensor 4 is located at the at least one compartment 30 which is designed
to receive the washing agent. Further, the sensor 4 is operatively associated with
the washing agent compartment 30, meaning by this that the sensor 4 is capable of
analyzing the contents of the compartment 30.
[0020] Detecting the type of washing agent before starting the washing cycle makes it possible
to adapt the washing cycle so as to optimize the properties of the washing agent itself.
The sensor 4, although it can detect the properties of solid washing agents, provides
the best results with liquid washing agents.
[0021] Although the embodiment described above is preferred, the sensor 4 might not be located
exactly at the compartment 30, but downstream of it, for example in an intermediate
chamber between the compartment 30 and the washing tank 2. In this case, the chamber
should be provided with blocking means so that the washing agent drawn from the compartment
30 can be allowed to enter or prevented from entering the washing tank 2.
[0022] The sensor 4 is operatively connected to a data processing unit which processes the
information provided by the sensor 4.
[0023] Advantageously, the data processing unit forms part of an electronic system that
controls the washing appliance 1.
[0024] The data processing unit may control the washing cycle parameters according to the
information provided by the sensor 4. The expression "control the washing cycle parameters"
means also the possibility of determining which step in the washing cycle is the best
for drawing the washing agent from the compartment 30 and feeding it into the washing
tank 2. Preferably, within the selected step, the washing appliance 1 is also able
to determine the best moment for drawing the washing agent from the compartment 30:
for example, at the beginning of the step, at the end of the step, or at another time.
[0025] In particular, the data processing unit activates the release of washing agent from
the at least one compartment 30 to the washing tank 2, said release occurring at a
predetermined step of the washing cycle, the choice of the step being determined on
the basis of the information received from the sensor 4. The information relates to
the chemical and/or physical properties of the washing agent located in the specific
compartment 30 whose contents are released into the washing tank. For example, for
an optimum effect, one washing agent may need to be fed in during pre-wash, while
another washing agent should be fed in during rinse, and so on. As mentioned above,
the Applicant has found that the optimum effect of traditional bleach is obtained
by releasing the bleach into the washing tank 2 during the main wash, while non-chlorine
bleach is best fed into the washing tank 2 during rinse or during a specific pre-wash.
In one particular non-limiting embodiment, the fact that the data processing unit
controls the washing cycle parameters may mean for example that detection of non-chlorine
bleach in the compartment 30 automatically causes the bleach to be released during
rinse and not during the main wash. Alternatively, detection of non-chlorine bleach
might cause the bleach to be released during the pre-wash, automatically starting
a specific pre-wash especially designed to optimize the properties of the non-chlorine
bleach. In the presence of non-chlorine bleach, the choice between the two possibilities
is left to the manufacturer and depends on how the washing appliance is programmed.
[0026] The data processing unit comprises means for comparing the chemical and/or physical
properties measured by the sensor 4 with the information stored in an archive and
associated in advance with the presence of a respective washing agent. Thus, the washing
appliance 1 can detect the presence of a certain washing agent that has been entered
in the archive.
[0027] The data processing unit has a user interface that provides information relating
to the washing agents detected.
[0028] Advantageously, the user interface of the data processing unit communicates to the
user interface the presence in the at least one compartment 30 of a washing agent
whose chemical and/or physical properties detected by the sensor 4 do not match those
expected for that specific compartment 30. This warns the user, for example, if bleach
or other washing aid is mistakenly placed in the compartment where the detergent should
be placed. In one particular embodiment comprising a plurality of compartments 30,
the washing appliance 1 may, on the basis of the information provided by the sensor
4, detect the contents of each compartment 30. The sensor 4 tells the washing appliance
in which compartment the detergent has been placed, in which compartment the fabric
softener has been placed, in which compartment the bleach has been placed (and whether
it is traditional or non-chlorine bleach), and so on. Thus, on the basis of the information
from the sensor 4, it is the washing appliance 1 that selects when and from which
compartment 30 the washing agent can be released.
[0029] In more general terms, the washing appliance releases the contents of the compartment
30 into the washing tank 2 only if the compartment contains a washing agent whose
chemical and/or physical properties detected by the sensor 4 match those of the washing
agent required by the washing cycle.
[0030] Different types of sensors may be provided.
[0031] In a first example embodiment, the sensor 4 comprises an optical sensor. The optical
sensor takes measurements based on the colour or turbidity of the washing agent located
in the respective compartment 30.
[0032] In another embodiment, the sensor 4 comprises an electrical conductivity sensor.
This type of sensor measures the electrical conductivity of the washing agent located
in the respective compartment 30. One possible disadvantage of an electrical conductivity
sensor used for this purpose is that it requires two electrodes that must be in physical
contact with the washing agent.
[0033] In the preferred embodiment, the sensor 4 comprises an atmospheric gas/vapour concentration
sensor.
[0034] The gas/vapour concentration sensor makes it possible, for example, to distinguish
whether the compartment contains traditional or non-chlorine bleach. Depending on
this information, the data processing unit activates a procedure whereby the washing
agent located in the compartment 30 is released to the washing tank 2 at a predetermined
step of the washing cycle.
[0035] Advantageously, according to this procedure, the washing agent is released:
- during the main wash if the sensor 4 has detected the presence of traditional bleach;
or
- during the rinse or pre-wash step if the sensor 4 has detected the presence of non-chlorine
bleach.
[0036] The concentration sensor distinguishes between traditional bleach and non-chlorine
bleach because of the different chemical composition of the two types of bleach. On
account of the different chemical composition, the vapours of the two types of bleach
are quite different. The possibility of distinguishing between the two types of bleach
resides in the capacity of the gas/vapour concentration sensor to detect a characteristic
component of each product (or, more generally, a different concentration of the same
component). In particular, traditional bleach is a solution of sodium hypochlorite
and water, while non-chlorine bleach is a solution comprising distilled water, hydrogen
peroxide and non-ionic surfactants.
[0037] Depending on the concentration of a particular gas/vapour to which the gas/vapour
concentration sensor is sensitive, the sensor increases the electrical conductivity
of a specific receptor connected to a transducer which converts the electrical variation
into a signal indicating the concentration of that gas/vapour. The concentration sensor
is sensitive to temperature and relative humidity. In order to minimize the influence
of these variables, there is a heating element which keeps the sensor at the optimum
temperature. Alternatively, there may be a sensor for measuring the temperature and
relative humidity and capable of compensating the value measured by the concentration
sensor.
[0038] A single compartment 30 might also be associated with two or more sensors 4 of different
kinds.
[0039] As mentioned above, the washing appliance 1 may comprise a plurality of compartments
30. For example, in the non-limiting example embodiment shown in Figure 1, the washing
appliance comprises four compartments: one for the pre-wash detergent, one for the
main wash detergent, one for the fabric softener and one for the bleach. The compartments
30 are separate from each other so that their contents cannot mix.
[0040] Advantageously, the four compartments are formed in a single drawer. The drawer may
be pulled out by the user to gain access to the compartments for the different washing
agents and then re-closed. The different compartments 30 might, however, be accessible
independently of each other: for example, they might be located in different drawers.
Further, each compartment 30 might form part of a feed line 3 that is independent
of the feed line of the other compartments 30.
[0041] Preferably, as illustrated schematically in Figure 2, all the compartments 30 are
connected to a single conduit 5 of the feed line 3. In the laundry washer trade, this
single conduit 5 is often referred to as loading hopper. Advantageously, the at least
one sensor 4 is located in the drawer housing, preferably at the top of the housing
at the at least one compartment 30.
[0042] In an example embodiment that is not illustrated, the sensor 4 is operatively associated
with at least two compartments 30 and, preferably, the sensor 4 is operatively associated
with all the compartments 30. In this case, all the compartments 30 are preferably
formed in the same drawer and the sensor 4 must be able to distinguish the information
from each compartment 30.
[0043] In another example embodiment, the washing appliance 1 comprises a plurality of sensors
4, each operatively associated with and located at a respective compartment 30.
[0044] Normally, during use, the user places in the respective compartments the different
washing agents to be used in the washing cycle.
[0045] The sensors analyse the washing agents and the washing appliance adapts the washing
cycle on the basis of this information provided by the sensors. For example, if the
substance located in the bleach compartment is a non-chlorine bleach, it is best released
into the washing tank during the rinse step or, alternatively, the washing cycle can
be adapted to include a specific pre-wash for this type of bleach. Traditional bleach,
on the other hand, is best released into the washing tank during the main wash.
[0046] The invention brings important advantages.
[0047] First and foremost, it allows the action of the washing agents, especially washing
aids, to be optimized.
[0048] Another important advantage is that it can prevent mistakes made by the user when
filling the compartments.
[0049] The invention can be modified and adapted in several ways without thereby departing
from the scope of the inventive concept.
[0050] Moreover, all details of the invention may be substituted by other technically equivalent
elements.
[0051] In practice, the embodiments of the invention may be made from any material, and
in any size, depending on requirements.
1. A washing appliance, designed preferably for household use, comprising:
- a washing tank (2) suitable for containing a washing liquid used for a washing treatment;
- a feed line (3) for feeding at least one washing agent, said feed line (3) leading
into the washing tank (2) and including at least one compartment (30) accessible by
the user who puts the washing agent into it;
the washing appliance being
characterized in that it comprises at least one sensor (4) for detecting predetermined chemical and/or
physical properties of the at least one washing agent, said sensor (4) being located
upstream of the washing tank (2) relative to the direction in which the washing agent
flows along the feed line (3).
2. The washing appliance according to claim 1, characterized in that the sensor (4) is located at and operatively associated with the at least one compartment
(30) designed to receive the washing agent.
3. The washing appliance according to claim 1 or 2, characterized in that the sensor (4) is operatively connected to a data processing unit which processes
the information provided by the sensor (4).
4. The washing appliance according to claim 3, characterized in that the data processing unit processes the parameters of the washing cycle according
to the information provided by the sensor (4).
5. The washing appliance according to claim 3 or 4, characterized in that the data processing unit activates the release of washing agent from the at least
one compartment (30) to the washing tank, said release occurring at a predetermined
step of the washing cycle, the choice of the step being determined on the basis of
the information received from the sensor (4) relating to the chemical and/or physical
properties of the washing agent located in the specific compartment (30) whose contents
are released to the washing tank (2).
6. The washing appliance according to claim 3 or 4 or 5, characterized in that the data processing unit comprises means for comparing the chemical and/or physical
properties measured by the sensor (4) with the information stored in an archive and
associated in advance with the presence of a respective washing agent.
7. The washing appliance according to any of the foregoing claims from 3 to 6, characterized in that the data processing unit communicates to a user interface the presence in the at
least one compartment (30) of a washing agent whose chemical and/or physical properties
detected by the sensor (4) do not match those expected for that specific compartment
(30).
8. The washing appliance according to any of the foregoing claims, characterized in that the at least one washing agent comprises a washing aid.
9. The washing appliance according to any of the foregoing claims, characterized in that the sensor (4) comprises an optical sensor.
10. The washing appliance according to any of the foregoing claims, characterized in that the sensor (4) comprises an electrical conductivity sensor.
11. The washing appliance according to any of the foregoing claims, characterized in that the sensor (4) comprises an atmospheric gas/vapour concentration sensor.
12. The washing appliance according to claim 11 when it depends directly or indirectly
on any of the claims from 3 to 7, characterized in that the gas/vapour concentration sensor distinguishes between traditional bleach or non-chlorine
bleach in the compartment (30), the data processing unit activating a procedure, depending
on this information, whereby the washing agent located in the compartment (30) is
released to the washing tank (2) said release occurring at a predetermined step of
the washing cycle.
13. The washing appliance according to claim 12,
characterized in that, according to said procedure, the washing agent is released:
- during the main wash if the sensor (4) has detected the presence of traditional
bleach; or
- during the rinse or pre-wash step if the sensor (4) has detected the presence of
non-chlorine bleach.
14. The washing appliance according to any of the foregoing claims, characterized in that it comprises a plurality of compartments (30).
15. The washing appliance according to claim 14, characterized in that the sensor (4) is operatively associated with at least two compartments (30), the
sensor (4) being preferably associated with all the compartments (30).
16. The washing appliance according to claim 14, characterized in that it comprises a plurality of sensors (4), each operatively associated with, and located
at, a respective compartment (30).
17. The washing appliance according to any of the foregoing claims, characterized in that it comprises a laundry washer or a dishwasher.