Note: Descriptions are shown in the official language in which they were submitted.
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Tablet Dispensing Device
Field of the invention
The present invention relates to a dispensing device for detergent tablets to
be introduced with the laundry in a washing machine.
Background of the invention
Detergent compositions formed as non particulate solids such as bars or
tablets or briquettes are known in the art. In the following, the term
"tablet" will
refer to any form of non particulate solids. The tablet provides a number of
advantages to both the consumer and the manufacturer. For example, the tablet
avoids spillage of the detergent composition. Furthermore, the tablet
eliminates
the need for the user to estimate the dosage of detergent composition required
and ensures that the correct dosage of detergent composition per wash cycle is
used by the user.
To further simplify handling and in order to maximize dissolution, thus
improving the performance of the detergent tablet, many detergent compositions
manufacturers provide the consumer with dispensing devices in which to piace
the detergent tablet prior to being placed in the washing machine. Indeed,
dispensing devices in the form of baskets or cradles are often utilized for
example in automatic dish washing machines to maximize the performance of
the tablet. Usually, these dispensing devices are based on a rigid cage
structure.
~4n example of a dispensing device for tablets with a rigid cage structure is
described in co-pending European Patent Application No. 95304115.9.
It has been found that the detergent tablet is slowly dissolved within these
dispensing devices based on rigid cage structures) especially when the
dispensing device is placed into a laundry washing machine together with the
laundry. Indeed, it is very likely that the dispensing device is covered by
the
(sundry during a wash cycle of the washing machine. Consequently, the wash
liquor is substantially prevented from directly reaching the dispensing device
to
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dissolve the detergent tablet. -This results in reduced dissolution of the
detergent
tablet in a laundry washing machine together with the laundry. By contrast, it
has
been found that a detergent tablet broken up during the wash cycle results in
an
improved dissolution of the detergent tablet in a laundry washing machine.
EP-A-0 473 532 describes a tablet dispensing device to be placed in a
washing machine for washing clothes. This device is a flexible bag-like body
containing in its interior a freely movable disintegrating body. This
disintegrating
body helps in pulverizing the detergent tablet during the wash cycle of a
laundry
washing machine. Consequently) the pulverized detergent tablet is dissolved
more quickly. Nevertheless, the disintegrating body is an additional and
separate
piece which has to be inserted into the bag-like body in the manufacturing
process before closing the dispensing device. This complicates the
manufacturing process of this dispensing device resulting in increased
manufacturing costs. Furthermore, this disintegrating body may damage the
drum of the washing machine. Indeed, the bag-like body does not protect the
drum from the disintegrating body which may be thrown against the drum e.g.
during the tumble-dry of the wash cycle.
EP-A-0 479 711 describes another tablet dispensing device to be placed in a
washing machine for washing clothes. This device comprises also a flexible
bag.
This bag has a mouthpiece defining an inlet opening for the detergent. The bag
further comprises a closing part opposite the mouthpiece. The closing part is
adapted to be releasably engaged with the mouthpiece forming a rigid
structure.
The tablet is broken up when the textile during the wash cycle presses the
tablet
against the rigid structure of the engaged mouthpiece and the closing part.
The
mouthpiece and the closing part have to be provided with an appropriate
engaging means. This complicates the manufacture, which increases the
manufacturing costs, and the handling of the dispensing device.
It is therefore an object of the present invention to provide a dispensing
device
providing an improved breaking up of the detergent tablet in laundry washing
machine without using additional disintegrating bodies in the dispensing
device.
Summary of the invention
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The present invention is a tablet dispensing device being liquid permeable.
The device comprises a first member, an opposing second member and
connecting means. The first member and the second member are substantially
rigid. The first member and the second member are connected to the connecting
means, the connecting means being flexible so that the distance between the
first member and the second member is variable allowing the first and second
members to come into close proximity. The first member and the second
member are movable in a substantial free manner from each other when the
dispensing device is placed in a laundry washing machine.
Brief description of the figures
Figure 1 is a perspective front view of an embodiment of the tablet dispensing
device according to the present invention.
Figure 2 illustrates a perspective front view of another embodiment of the
tablet dispensing device according to the present invention.
Figure 3a shows a top view of a first member andlor a second member of the
tablet dispensing device in an embodiment according to the present invention.
Figure 3b shows a side view a first member andlor a second member of the
tablet dispensing device in an embodiment according to the present invention.
Figure 4a is a perspective front view of another embodiment of the tablet
dispensing device according to the present invention. Figure 4b shows a top
view of the first member and the second member of the tablet dispensing device
of Figure 4a.
Figures 5 to 6 show top views of a first member andlor a second member of
the tablet dispensing device according to the present invention.
Figure 7 illustrates a perspective front view of another preferred embodiment
of the tablet dispensing device according to the present invention.
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Detailed description of the invention
In the following any form of non particulate solids such as bars or tablets or
briquettes will be encompassed by the term "tablet". The tablet is made from a
-
detergent composition for dish or laundry washing. The tablet may have any
shape or dimension. Preferably, the solid, non particulate tablet is
symmetrical to
ensure the uniform dissolution of the tablef< in the wash liquor.
According to the present invention the detergent tablet may comprise any
ingredients known in the art. Such ingredients may include surfactants, suds
suppressors, bleaches, chelants, builders, enzymes, fillers and perfumes.
According to the present invention the detergent composition of the tablet is
prepared in its granular or particulate form and then formed into tablets of
the
desired shape and size by any one of the methods known in the art. Suitable
methods include compression, extrusion and casting. The detergent composition
may be homogeneously distributed throughout the tablet or may comprise
distinct layers of certain detergent ingredients.
The preferred embodiment of a tablet dispensing device (10) according to the
present invention is shown in Figure 1. This dispensing device is for
retaining a
detergent tablet and for dispensing a detergent tablet in a wash liquor of a
laundry washing machine. The device is liquid permeable so that a liquid
passing
through the device dispenses the detergent tablet when the device retains a
detergent tablet. The device comprises a first member (11 ), a connecting
means
(12) and a second member (14). The first member is connected to one end of
the connecting means. The second member is also connected to the connecting
means on an opposite end of the connecting means with respect to the first
member. The connecting means is flexible so that the distance between the
first
member and the second member is variable. The connecting means allows the
first member and the second member to come into close proximity. As herein
referred to, "closeproximity" is such that a detergent tablet is squeezed
between
the first member and the second member when the detergent tablet is placed
within the dispensing device.
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Preferably, the connecting means (12) is a net, as shown in Figure 1. The net
comprises orifices (15) of appropriate size. The "appropriate size" is such
that
the tablet, when inserted into the dispensing device (10), is not able to
escape
through the net until the detergent tablet is sufficiently reduced in size by
breaking up andlor dissolution in the wash cycle. The detergent tablet is
sufficiently reduced in size when no poor dissolution of the reduced detergent
tablet is observed in the wash cycle. Preferably, the net comprises a slit to
insert
a detergent tablet into the dispensing device. The slit may be obtained by a
net
which is interrupted. For example, this may be achieved by a superimposed net
connected together only to the first member (11) and the second member {14).
Thus, the tablet is inserted through the superimposed region of the net
between
the first member and the second member.
In an alternative embodiment, the connecting means (12) is flexible and
resilient. For example this may achieved by connecting means in form of a
spring
or of bellows. An example of connecting means formed as bellows is shown in
Figure 2. The connecting means of Figure 2 comprises a plurality of arms (16).
The tree space between the arms is such that a detergent tablet inserted into
the
dispensing device is not able to escape through the connecting means until the
detergent tablet is sufficiently reduced in size by breaking up and/or
dissolution
in the wash cycle. The connecting means shaped as bellows is hinged at the
connection (18) with the first member (11) and the second member (14).
Preferably) each arm of the bellows further comprises a hinge ( 19) located on
each arm half way between the first member and the second member. The
bellows may fold inwards to interior of the dispensing device or outwards away
from the interior of the dispensing device. The connecting part in this -'
embodiment is flexibly and resiliently deformed along the hinges (18) and (19)
allowing the first member and the second member to come into close proximity
to each other. This enables the squeezing of the detergent tablet between the
first member and the second member when the detergent tablet is inserted into
the dispensing device according to the present invention. This facilitates the
breaking up of the detergent tablet.
The material of the connecting means (12) has to be sufficiently resistant to
the temperatures of the wash liquor reached during the washing. Preferably)
the
material of the connecting means is a woven or non-woven material made from
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natural or synthetic fibres or a mixtures of such fibres. The material of the
connecting part may also be extruded or co-extruded films, provided with
perforations. The material of the connecting means may also be plastic
material,
like elastomers) or made of paper or other porous, water resistant cellulosic
material. Possible elastomeric materials are, for example, polypropylene)
polyethylene or polyester. All these elastomers ensure enough compatibility
with
the wash liquor and resistance to the temperatures mentioned before. However,
metal is another possible material for the connecting means. A metal material,
like aluminium is especially suitable when the connecting means is in a form
of a
spring. It is preferable then that the metal material is stainless steel or it
is
protected by a layer of plastic on the outside. The metal material has the
advantage that it allows an easier variation in shape of the connecting means
itself. If the material used for the connecting means does not itself have
sufficient
resistance to water, it may be provided with a coating making it water
resistant.
For example, in the case of porous paper, the coating may consist of a latex
based binder associated with a hydrophobic substance.
According to the present invention the first member (11 ) and the second
member (14) are substantially rigid. As herein referred to, "substantially
rigid"
mean that the first member and the second member are rigid or hard enough to
help to break-up the detergent tablet placed within the dispensing device. The
first member and the second member are movable in a substantial free manner
from each other when the dispensing device is placed in a laundry washing
machine. As herein referred to, "substantial free movements" are such that the
first member and the second member move independently from each other
whereby their movement is only limited by the connection to the connecting
means. The substantial free movements of the first member and the second
member help to break up the detergent tablet whenever the first member and the
second member come into close proximity.
The first member and the second member come to close proximity when the
dispensing device (10) is agitated during a wash cycle within the drum of the
laundry washing machine. Indeed, the distance between the first member and
the second member is variable with the agitation during a wash cycle due #o
the
flexible connecting means. Thus, the detergent tablet is repeatedly squeezed
between the first member and the second member during the wash cycle. The
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repeated squeezing of the detergent tablet within the dispensing device is
allowed by the substantial free movements of the first member and the second
. member: The squeezing of the detergent tablet is further aided by the weight
of
at least part of the wash liquor loaded textiles in the drum of the laundry
washing
machine. It has been found that this repeated squeezing of the detergent
tablet
between the first member and the second member improves the breaking up of
the detergent tablet. This improved breaking up of the detergent tablet is
achieved without the need of an additional freely movable disintegrating body
within the dispensing device. The breaking up of the detergent results in an
improved dissolution of the detergent tablet, especially when the detergent
tablet
contains surtactant. Indeed, surfactant containing detergent tablets are
usually
poorer in dissolution than detergent tablets not containing surfactants.
To improve the rigidity of the first member (11 ) and/or of the second member
(14), the first member (11 ) andlor the second member (14) may preferably
comprise ribs (20). The ribs are located on the side of the first member and
the
second member directed to the interior of the dispensing device, as shown in
Figure 1. As a preferred option, the ribs converge towards the midpoint of the
first member and the second member) as shown for example in Figure 1. The
midpoint of the first member andlor of the second member may further comprise
a circular ring (21) onto which the other ribs converge.
In a preferred embodiment of the present invention, the first member (11 )
andlor the second member (14) may be a solid wall or an interrupted wall. The
interrupted wall is a wall comprising at least one opening (22) through the
thickness of wall. The first member andlor the, second member being
interrupted
walls further improves the liquid permeability of the dispensing device, and
consequently improves the dissolution of the detergent tablet. The size of the
opening (22) is such that the tablet, when inserted into the dispensing
device, is
not able to escape through the opening without the detergent tablet being
sufficiently broken -up andlor sufficiently dissolved during a wash cycle of
the
laundry washing machine.
it is possible to use deformable and resilient materials for the first member
(11 ) and/or the second member (14), but hard enough to allow the helping in
the
breaking up of the detergent tablet. A deformable first member andlor second
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member reduces the noise of the device (10) during the agitation in the drum
of
the washing machine. The resilient first member andlor second member insure
that the opening (22) is always held open as wide as possible during the
washing. Such a material is, for example, polyurethane (PU) or other
elastomers.
As a preferred option the size of the opening (22) can be flexibly and
resiliently enlarged to facilitate the introduction of a detergent tablet into
the
dispensing device. A possible example of an opening which can be flexibly and
resiliently enlarged is shown in Figures 1 and 2. The opening on the first
member
(11 ) andlor the second member (14) can be enlarged through the hinged
movable elements (23). The elements (23) are movable around the interrupted
line (24). These elements (23) are flexed towards the interior of the
dispensing
device when a detergent tablet is inserted through the opening. Once the
detergent tablet is inside the dispensing device, the eiements (23)
resiliently flex
back to the original position shown in Figure 1 or 2. The shape of the first
member (11) and of the second member (14) is preferably rounded to avoid to
cause scratches in the laundry through sharp edges.
In a further embodiment, the first member (11 ) and/or the second member
(14) comprise at least a hinged element (30). The hinged element allows the
insertion of a tablet into the dispensing device, but impedes that the
inserted
tablet exits from the dispensing device. Indeed, the hinged element turns only
towards the inside of the dispensing device for the insertion of the tablet at
the
hinge (34). In practice the hinged element works like a trap door. The hinged
element (30) may comprise an opening (22). As shown in the top view of Figure
3a, the first andlor the second member comprise two hinged elements opposed
to each other and both connected to a rim (32). Both hinged elements comprise
-openings (22). -
Figure 3b shows the first member andlor the second member in another
preferred embodiment, in which the hinged elements (30) and (30') turn in
opposite directions. Indeed) the hinged element (30) turns towards the inside
of
the dispensing device, whereas the opposing hinged element (30') turns to the
outside of the dispensing device. In the rest position) when the hinges are
not
turned around the hinge, the hinged elements (30) and (30') are at least
partially
overlapping. These hinged elements (30) and (30'), turning in opposite
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directions, allow an easy insertion of a tablet into the dispensing device)
but
reduce the risk that the tablet once inserted into the dispensing device
escapes
from inside the dispensing device.
Figure 4a illustrates another preferred embodiment of the first member (11)
and/or second member (14) comprising a hinged element (30). The hinged
element is made of a bent arm (33}) whereby both ends of the bent arm are
hinged to the rim (32) the hinges (34). P-referably, the first member and/or
the
second member comprise several hinged bent arms (33) placed around the rim
(32), as shown in Figure 4a. Figure 4b shows that the first and the second
member may be made out of one piece. The first member comprisesJthe hinged
elements. The second member is connected to the rim (32) through breakable
tabs (35), as shown in Figure 4b. The dispensing device shown in Figure 4a is
achieved by separating the second member from the rim along the breakable
tabs and attaching the connecting means (12) between the first member and the
second member.
In another alternative, but preferred embodiment of the present invention, the
first member (11) and/or the second member (14) is an interrupted wall
comprising impellers (40) 50, 60). Top views of a first member or a second
member of a dispensing device according to the present invention are shown in
Figures 5 and 6. Figure 7 shows an even more preferred embodiment of a tablet
dispensing device according to the present invention. The first member (11 )
and
the second member (14) comprise impellers (60) which are in a curved form.
Preferably, the first member and the second member comprise six such
impellers. The connecting means is the net as described above comprising a
slit
allowing the insertion of a detergent tablet into the dispensing device. The
advantage of the first member and the second member being an interrupted wall,
as described before, or having impellers resides in the fact that they further
break up the detergent tablet before parts of the detergent tablet get on the
laundry or in the wash liquor. This means, that the interrupted wall or these
impellers further contribute to the better dissolution of the detergent tablet
in the
wash cycle.
Another important advantage of the tablet dispensing device (10) according to
the present invention is that the flexible connecting means (12) allows to
bring
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the dispensing device in a collapsed configuration. The collapsed
configuration
of the device (10) reduces to a minimum the space needed in a package to
contain the detergent tablet and the device (10). The device (10) in collapsed
configuration can be easily put onto or inside the packages. For example, the
device (10) being in collapsed configuration can be fastened outside or put
inside the package. Preferably) the dispensing device is fastened or kept in a
tight bag to hold the collapsed configuration. The packages containing the
detergent tablets and the collapsed tablet dispensing device have mainly the
same dimensions and occupy the same volume as those packages which do not
contain the tablet dispensing devices. Also, the packaging may comprise a
greater amount of detergent tablets for a given package volume due to the
reduced volume of the dispensing device. Therefore, packaging and storing
costs can be reduced.
