Field of the invention
[0001] The present invention relates to laundry treatment appliances or machines. In more
detail, the present invention refers to appliances for drying laundry, both for domestic
and professional use. More particularly, the present invention relates to a de-fluff
filter.
Background of the invention
[0002] Drying and washing/drying laundry machines - which will be referred to simply as
laundry machine in the following - typically comprise a casing substantially parallepiped-shaped.
The casing accommodates a laundry treating chamber, comprising a drum, generally rotatable,
apt to contain the laundry to be dried, in the case of a washing/drying laundry machine,
the drum is rotatably contained in a tub. A front panel of the casing has a loading
opening to access the treating chamber for loading/unloading the laundry, and a door
is provided for closing the loading opening, particularly during the laundry machine
operation.
[0003] The casing also accommodates the electrical, electronic, mechanical, and hydraulic
components necessary for the operation of the laundry machine. Particularly, laundry-drying
capable machines features an air circuit (comprising, for example, fans, air ducts,
a moisture condensing unit, a heating unit,
etc.) adapted to heat air, blow it into the drum where it removes moisture from the laundry,
suck out from the drum the moisturized air, de-moisturize the air and reiterate such
actions thereby performing a laundry drying cycle.
[0004] During a washing and/or drying process, the laundry under treatment typically loses
lint particles or fluff. The fluff is generally light and tiny, thus it can be brought
out from the drum by the hot drying air flowing therein and then into the air circuit.
[0005] Once in the air circuit, the fluff is likely to accumulate therein, thereby possibly
obstructing air ducts of the air circuit or negatively affecting the operation of
one or more of its components (e.g., fluff may deposit on a fan, to the extent of
possibly causing the latter to operate with a lower efficiency or completely stop
it). In general, fluff accumulation has a detrimental effect on the laundry drying
machine operation.
[0006] Therefore de-fluff filters have been designed for the purpose of retaining the fluff
so as to prevent it from damaging the laundry machine components. Nevertheless, the
de-fluff filter needs to be periodically cleaned to avoid it to get clogged, event
that may reduce the laundry machine efficiency or even cause a laundry drying machine
malfunction, at least of the air circuit thereof. To this purpose, the de-fluff filter
is usually removably accommodated in a filter seat within the air circuit, for example
in a position located at the front of the casing in a top portion thereof, i.e. in
positions that are easily reachable by a user.
[0007] Notwithstanding the implementation of meticulous de-fluff filter maintenance, fluff
may still amass within the de-fluff filter during the course of a single laundry drying
machine operation in a quantity that may affect the efficiency of the laundry machine.
[0008] Particularly, fluff trapped in the de-fluff filter may hinder the flow of air within
the air circuit of the laundry drying machine. For example, trapped fluff may reduce
a flow rate through the de-fluff filter, thus causing localized pressure peaks and
drops in the air circuit and subsequent localized /or temperature rise along the air
circuit.
[0009] EP 2 843 103 A1 discloses a laundry machine with a de-fluff filter, which comprises a filter box
and a lid defining a hollow chamber within. A filtering mesh is arranged on an outlet
portion of the box on a transversal sidewall. The lid comprises air guiding blades
protruding from a lower side of the lid towards the inside of the filter box, subdividing
the hollow chamber of the filter box in sub-chambers. The sub-chambers have a sectional
area that increases along the drying air flow direction path, in such a way to distribute
evenly the drying air flow inside the filter box for homogenously directing the drying
air flow towards the filtering mesh.
[0010] US 5,651,188 A discloses a lint storage system comprising a lint basket with one hollow chamber
therein. The lower and side surfaces of the basket comprise outlet openings covered
with filter elements, wherein the size of the outlet openings increases from the air
inlet end of the basket to the outlet end of the basket.
[0011] It would be therefore desirable to increase the number of laundry drying processes
performable between two subsequent de-fluff filter cleaning operations with a sufficient
degree of energy efficiency. In particular, it would be desirable to achieve that
goal limiting or even avoiding, the increase of the filter seat.
Summary of invention
[0012] The Applicant has tackled the problem of devising a laundry machine comprising a
de-fluff filter arrangement capable to overcome, at least partly, the drawbacks of
the prior art.
[0013] The Applicant has devised a de-fluff filter that is easy to insert into, and to remove
out of a corresponding housing, and which is able to ensure a substantially homogenous
flow rate of air therethrough during the laundry machine operation.
[0014] One aspect of the present invention proposes a laundry machine adapted to dry laundry
by means of a flow of drying air is proposed. The laundry machine comprises: a casing;
inside the casing, a laundry treating chamber adapted to contain the laundry to be
dried; an air circuit in fluid communication with the laundry treating chamber through
an inlet opening, and defining an air-path for the flow of drying air between said
inlet and outlet openings; a filter housing for removably accommodating a de-fluff
filter, said filter housing being provided in the air-path and being accessible through
a housing aperture. The de-fluff filter is arranged for trapping fluff or lint particles
carried by the flow of drying air crossing said de-fluff filter, the de-fluff filter
comprises a filtering element and a hollow chamber which comprises an inlet aperture
and an outlet portion. The de-fluff filter further comprises an airflow diverter which:
divides the hollow chamber of the de-fluff filter in a first portion and a second
portion, and diverts the flow of drying air entering the de-fluff filter towards the
first portion of the hollow chamber or towards the second portion of the hollow chamber
according to an amount of fluff currently trapped in the at least one filtering element.
[0015] The airflow diverter comprises at least one filtering element for filtering the flow
of drying air entering the first portion of the hollow chamber of the de-fluff filter
thereby trapping fluff or lint particles.
[0016] Preferred features of the present invention are set in the dependent claims.
[0017] According to the invention, the majority of drying air flow entering the de-fluff
filter is directed to the first portion of the hollow chamber in a first part of a
drying process. The airflow diverter is arranged for diverting the flow of drying
air entering the de-fluff filter from the first portion of the hollow chamber towards
the second portion of the hollow chamber according to an amount of fluff currently
trapped in first portion of the hollow chamber.
[0018] In an embodiment of the invention, the first portion and the second portion of the
hollow chamber define, for the flow of drying air, two paths causing a different amount
of energy losses to the fluid portions entering the first and the second portion respectively.
[0019] In an embodiment of the invention, the amount of energy losses caused by the first
portion is lower than the amount of energy losses caused by the second portion.
[0020] In an embodiment of the invention, during a laundry drying process, the progressive
accumulation of fluff or lint particles in the first region of the hollow chamber
increases the amount of energy losses to the fluid portion entering the first portion
up to make such amount greater than the amount of energy losses caused by the second
portion.
[0021] In an embodiment of the invention, the airflow diverter traps fluff or lint particles
at least up to a threshold amount that causes substantially the whole airflow to divert
from the first region to the second region of the hollow chamber.
[0022] In an embodiment of the invention, said threshold amount of fluff or lint particles
is a function of at least one among: a size of the first region, a size of the hollow
chamber, a size of the airflow diverter and a size of a filtering element provided
in the airflow diverter or in the de-fluff filter.
[0023] In an embodiment of the invention, the airflow diverter comprises a peripheral frame
and at least one separating element, the peripheral frame and at least one separating
element defining two or more filtering elements.
[0024] In an embodiment of the invention, the peripheral frame is integral with the at least
one separating element.
[0025] In an embodiment of the invention, the peripheral frame and the at least one separating
element comprise a first half and a second half, each half being symmetrical to the
other and designed to couple with the other half along a longitudinal symmetry plane
of the airflow diverter.
[0026] In an embodiment of the invention, the airflow diverter is removably mounted in the
hollow chamber of the de-fluff filter.
[0027] In an embodiment of the invention, the airflow diverter further comprises at least
one foot element arranged for coupling with the de-fluff.
[0028] In an embodiment of the invention, the de-fluff filter further comprises at least
one foot receptacle. Preferably, the at least one foot element is arranged for coupling
with said at least one foot receptacle.
[0029] In an embodiment of the invention, the de-fluff filter further comprises one or more
retaining brackets for holding the airflow diverter in a working position within the
hollow chamber.
[0030] In an embodiment of the invention, the de-fluff filter further comprises a filter
box and a lid hinged to the filter box for pivoting from an opening position to a
closed position thereby selectively closing a top aperture of the filter box, the
hollow chamber being defined by the filter box and by the lid in the closed position.
Preferably, the airflow diverter is arranged for being flush both with the lid and
with a bottom wall of the filter box opposite to the lid.
[0031] In an embodiment of the invention, the lid comprises a plurality of lid ridges protruding
towards the filter box once the lid is in the closed position. Preferably, the filter
box comprises corresponding box ridges protruding towards the lid once the lid is
in the closed position, the lid ridges being arranged for interspersing with the box
ridges once the lid is in the closed position thereby forming a meandering path capable
of hindering the passage of fluff.
[0032] In an embodiment of the invention, the hollow chamber is delimited by a guiding wall
and a sidewall, the airflow diverter being arranged therebetween so as to form with
at least one of said guiding wall and sidewall a path having a convergent portion
along the direction of the flow of air.
[0033] In an embodiment of the invention, the airflow diverter is movable from a first position,
in which the airflow is directed into a first portion of the de-fluff filter, to a
second position, in which the airflow is directed into a second portion of the de-fluff
filter.
[0034] In an embodiment of the invention, the airflow diverter is deformable between a rest
configuration, in which the airflow is directed into a first portion of the de-fluff
filter, and a deformed configuration, in which the airflow is directed into a second
portion of the de-fluff filter.
Brief description of the annexed drawings
[0035] These, and others, features and advantages of the solution according to the present
invention will be better understood with reference to the following detailed description
of some embodiments thereof, provided for illustrative and not restrictive purposes,
to be read in conjunction with the attached drawings. In this regard, it is expressly
intended that the drawings are not necessarily to scale and that, unless specified
otherwise, they simply aim to conceptually illustrate the structures and procedures.
In particular:
Figure 1 is a perspective view of a laundry machine according to an embodiment of the present
invention;
Figure 2A is a perspective view of the laundry machine of Figure 1, showing a top thereof in exploded view;
Figure 2B is a perspective view of a base element of the top of the laundry machine according
to an embodiment of the present invention;
Figure 3A is a perspective view of a de-fluff filter according to an embodiment of the present
invention;
Figure 3B is a perspective view of a de-fluff filter according to an embodiment of the present
invention with its lid;
Figure 3C is a top view of a de-fluff filter according to an embodiment of the present invention
shown with a lid and an airflow septum removed;
Figure 3D is a cross-sectional top view along section plane IIID of the de-fluff filter of Figure 3A according to an embodiment of the present invention shown with a lid removed and
the airflow septum inserted,
Figure 4A is a cross-sectional front view along section plane IVA of a de-fluff filter according to an embodiment of the present invention;
Figure 4B and 4C are a close up views of Figure 4A showing the coupling between a filter box and a lid of a de-fluff filter according
to an embodiment of the present invention;
Figures 5A and 5B are a side view and a top view, respectively, of an airflow septum according to an
embodiment of the invention;
Figure 6 is a chart showing air pressure as a function of time during operation of a laundry
machine according to an embodiment of the invention and of a laundry machine known
in the art, and
Figure 7 is a chart showing capillary temperature as a function of time during the operation
of a laundry machine according to an embodiment of the invention and of a laundry
machine known in the art.
Detailed description of preferred embodiments of the invention
[0036] With reference to the drawings,
Figure 1 is a perspective view of a laundry machine, globally denoted as
100, according to an embodiment of the present invention.
[0037] The laundry machine
100 comprises a laundry treatment chamber
105 for accommodating the items to be dried or washed and dried, such as clothes, garments,
linen, and similar laundry items. Preferably, the laundry treatment chamber
105 includes a drum (not shown) rotatably mounted inside a machine cabinet or casing
110, and in case the laundry machine
100 is a washing/drying laundry machine the drum is arranged within a tub (not shown)
housed in the machine casing
110.
[0038] The casing
110 generally accommodates all the electrical, electronic, mechanical, and hydraulic
components necessary for the operation of the laundry machine. The casing
110 has generically a parallelepiped shape, with a front wall
115, two side walls
120 (only one visible in
Figure 1), a rear wall (not visible), a basement and a top element, or simply top
125. The front wall
115 is provided with an opening for accessing the drum and with an associated door
117 for closing the opening. In the upper part of the front wall
115, a machine control panel
130 is located, and, aside the control panel
130, a drawer
135 is provided, which is part of a washing treatment products dispensing arrangement,
for loading laundry washing treatment products like detergents and softeners. The
top
125 closes the casing
110 from above, and defines a worktop.
[0039] In one embodiment of the invention, a de-fluff filter (aesthetic) cover
140 is exposed on the control panel
130 on the front wall
115, e.g. above the drawer
135, and flushing therewith.
[0040] Preferably, the de-fluff filter cover
140 may comprise a pushbutton portion
145 for actuating a release of the de-fluff filter
218 from its working position (as described in the following).
[0041] Reference is now made to
Figures 2A and
2B, which are a perspective views of the laundry machine
100 with its top
125 in exploded view and a perspective view of a base element
205 of the top
125 with some parts removed.
[0042] In one embodiment of the invention, the top
125 integrates part of an air circuit adapted to circulate drying air across the laundry
treating chamber 105 for drying the laundry stored therein (as described below).
[0043] The top
125 comprises the base element
205, which has an inlet opening
210 and an outlet opening
215, the inlet opening
210 being in fluid communication with the laundry treatment chamber
105 through a chamber outlet, the outlet opening
215 being in fluid communication with a fan arrangement
216.
[0044] The fan arrangement
216 comprises a fan and a corresponding fan duct, the fan produces the drying airflow
inside the air circuit by sucking drying air from the outlet opening
215 and blowing the drying air into the laundry treatment chamber
105, the outlet opening
215 and the laundry treatment chamber
105 being both fluidly connected to the fan arrangement
216.
[0045] In the region of the base element
205, preferably near the front-left corner thereof, a filter housing
217 is provided.
[0046] The filter housing
217 is suitable to house a de-fluff filter
218 (described in greater detail below).
[0047] Preferably, the filter housing
217 has roughly a right trapezoid outline in plan view (e.g., similar to a grand piano),
with a shorter sidewall
217a (corresponding to a lesser base of the right trapezoid) in fluid communication with
the chamber outlet by means of the inlet opening
210, and a larger sidewall
217b (opposite to the shorter sidewall
217a, and corresponding to a greater base of the right trapezoid) that has a housing aperture
219 opened on the machine front wall
115 preferably in a separating wall
205a of the base element
205.
[0048] Preferably, the housing aperture
219 is provided in a separating wall
205a provided adjacent to the control panel
130, even more preferably above the drawer
135 for allowing the insertion of the de-fluff filter
218.
[0049] Moreover, the filter housing
217 comprises a right sidewall
217c substantially corresponding to a portion of a lateral sidewall of the base element
205 of the top
125 (and corresponding to the right leg of the right trapezoid) and a transversal opened
side
217d, preferably inclined (opposite to the right sidewall
217c and corresponding to the inclined leg of the right trapezoid).
[0050] In one embodiment of the present invention, the inlet opening
210 is fluidly connected to an adapter element
212, which is provided to fluidly connect the inlet opening
210 with the filter housing
217 and the de-fluff filter
218 (when inserted in the filter housing
217).
[0051] Preferably, but not limitatively, the adapter element
212 may be a parallelepiped-shape element adapted to be coupled with the base element
205. The adapter element
212 further comprises conical or cylindrical passage(s) having two opposite apertures
to fluidly connect the inlet opening
210 with the de-fluff filter
218.
[0052] The adapter element
212 may be made of any suitable material, e.g. a polymeric material, and is coupled with
the base element
205 by means of any suitable coupling arrangement, e.g. by tightly fitting (preferably
in an airtight manner) a rear portion of the filter housing
217 (adjacent to the shorter sidewall
217a).
[0053] In a preferred embodiment of the invention, the aperture facing the filter housing
217 of the adapter element
212 is surrounded by a gasket element
212a which protrudes towards the inside of the filter housing
217.
[0054] In alternative embodiments of the present invention in which the adapter element
212 is not provided, and an alternative gasket element may be directly provided around
the inlet opening
210 for directly coupling with the de-fluff filter
218.
[0055] In one embodiment of the present invention, the transversal opened side
217d comprises a frame
220 that defines a plurality of side windows
220a separated one from the other by separating elements, such as for example mullion
elements
220b, preferably prism-shaped. Preferably, at the frame
220 housing grooves (not visible in
Figures 2A and
2B) adapted to house an auxiliary filter
221 are provided.
[0056] Advantageously, a plurality of flap elements
222 may be provided. The flap elements
222 protrude from the frame
220 opposite to the filter housing
217 in order to direct the drying airflow exiting the transversal opened side
217d towards the rest of the air circuit defined in the top
125.
[0057] In the central region of the base element
205, there is accommodated a first heat-exchanging unit, such as a moisture condensing
element
225, for example comprising an evaporator of a heat pump apparatus.
[0058] The moisture condensing element
225 is adjacent to the transversal opened side
217d, and thus the external surface of the former is in fluid communication with the latter.
[0059] Next to the moisture condensing element
225, opposite to the filter housing
217, there is provided a second heat-exchanging unit, such as a drying air heating element
230, for example comprising a condenser of the heat pump apparatus.
[0060] The moisture condensing element
225 has the function of dehydrating the drying air, by cooling it down; the drying air
heating element
230 has instead the function of heating the dehydrated drying air.
[0061] A compressor (not shown) for the heat pump may be attached to the base element
205 in correspondence of the front-right corner thereof, the body of the compressor protruding
from below the base element
205.
[0062] In an alternative embodiment, the compressor may be located in the bottom of the
casing
110, attached to the basement of the laundry machine
100, and be fluidly connected to the moisture condensing element
225 accommodated in the top
125 by means of flexible pipes that preferably run along a rear corner of the casing
110 or along the laundry treatment chamber
105 of the laundry machine
100.
[0063] In a different embodiment of the present invention, the laundry machine
100 may comprise an air-air or an air-water heat exchanger apparatus and an electric
heater instead of the heat pump apparatus.
[0064] The base element
205 of the top
125 is covered by an inner panel
235, that covers essentially the moisture condensing element
225, the drying air heating element
230 and the de-fluff filter
218.
[0065] The top
125 is completed by an outer (aesthetic) panel
240.
[0066] The base element
205 and the inner panel
235 define an air-path that conveys the moisture-laden air coming from the laundry treatment
chamber
105 (through the inlet opening
210) towards the de-fluff filter
218, preventing the moisture-laden air from entering directly the moisture condensing
element
225 or the drying air heating element
230 (i.e., before being filtered by the de-fluff filter
217), and then the drying airflow follows the air-path from the de-fluff filter
218 to the heating element
230, passing through the moisture condensing element
225, and eventually reaching the outlet opening
215.
[0067] Preferably, the top
125, once assembled, forms a unit that is ready to be mounted to the casing
110, simply by placing it in the correct alignment, so that the openings
210 and
215 matches the chamber outlet and an intake of the fan arrangement
216, respectively, thus realizing a closed air circuit comprising the laundry treatment
chamber
105 and the air-path defined by the base element
205 and the inner panel
235, and the fan arrangement
216. The top
125 may then be secured to the casing
110 by conventional means (e.g., by means of gluing, screwing or other connecting/fastening
means).
[0068] When the laundry machine
100 is operated in dryer mode (i.e., for drying items stored in the drum), drying air
(i.e., warm and dry air) is typically caused to flow through the drum
105 inside the laundry treating chamber
105, where the items to be dried are contained.
[0069] The drying air binds to moisture particles from the laundry and/or dispersed within
the laundry treating chamber
105 and carries them away. The drying air may also carry away fluff (e.g., comprised
in and/or generated from the laundry during laundry treating processes) from the laundry
together with moisture particles.
[0070] After exiting the drum through the chamber outlet, the flow of now moisture-laden
drying air passes through the de-fluff filter
218 where substantially any fluff carried by the drying airflow together with moisture
particles is caught and remains trapped.
[0071] Instead, the moisture-laden drying air is conveyed towards the moisture condensing
element
225, where the moisture-laden drying air is at least partially dried, i.e. dehydrated,
and such dehydrated drying airflow is then heated by the air heating element
230 through which the drying airflows, which heats the drying air up to a drying temperature
(e.g., set by a user through the control panel 130 via the selection of a drying program).
[0072] Then the drying air is sucked by the fan through the fan intake and is caused to
pass again through the drum
105 drying the laundry therein stored and then repeating the cycle just described.
[0073] Considering now
Figures 3A to
3D, they are views of the de-fluff filter
218 according to embodiments of the present invention shown with and without a lid
306.
[0074] It should be noted that the de-fluff filter
218 is shown with also the aesthetic cover
140 removed in the following figures.
[0075] The de-fluff filter
218 is designed to be inserted inside the filter housing
217 preferably through the housing aperture
219 exposed on the front wall
115. Preferably, the de-fluff filter
218 is designed such as an extractable drawer.
[0076] The de-fluff filter
218 comprises a filter box
303, a cover element, such as for example a lid
306, and in addition it may preferably comprise a closing element, such a swinging bulkhead
309, an ejection device (not shown), and a locking element (not shown).
[0077] The filter box
303 has a parallelepiped shape, preferably with a roughly rectangular trapezoid base.
For example, the filter box
303 of the filter housing
217 may have a shape similar to that of a grand piano, with a rear sidewall
303a, a front sidewall
303b, a first transversal sidewall
303c, a second transversal sidewall
303d, preferably curved, and a bottom wall
303e. The sidewalls
303a, 303b, 303c, 303d delimit a top aperture
303t of the filter box
303. The filter box
303 may be made in any suitable material, such as for example a suitable polymer (e.g.,
Polypropylene PP).
[0078] Preferably (as can be appreciated in
Figure 2B), the filter box
303 is designed in such a way that, once the de-fluff filter
218 is inserted into the filter housing
217, the former substantially tightly fits the latter. Even more preferably, the sidewalls
303a and
303c are adapted to substantially flank the sidewalls
217a and
217c, respectively, of the filter housing
217 and may contact them, while the front sidewall
303b substantially closes the housing aperture
219 and the second transversal sidewall
303d faces the transversal opened side
217d of the filter housing 217, preferably remaining separated therefrom.
[0079] Preferably, the filter box
303 is designed in such a way that its second transversal sidewall
303d remains spaced apart from the transversal opened side
217d of the filter housing
217, thus defining a gap between the second transversal sidewall
303d and the transversal opened side
217d. Within the gap a housing for receiving, preferably in a sliding manner, the auxiliary
filter
221 (the housing being not detailed in the
Figures).
[0080] The second transversal sidewall
303d operates substantially as a filtering portion and as an outlet portion of the de-fluff
filter
218. The second transversal sidewall
303d comprises a frame
318 that encloses a plurality of filtering windows
318a separated from each other by separating elements, such as for example box mullion
elements
318b, preferably parallelepiped shaped. The box mullion elements
318b extend from a lower portion of the frame
318 (at the bottom wall
303b) of the filter box
303 up to a higher portion of the frame
318 (at the top aperture
303t). Advantageously, the box mullion elements
318b are designed to align with the mullion elements
220b of the transversal opened side
217d (once the de-fluff filter
218 is inserted into the filter housing
217), in such a way to not to hinder the drying airflow.
[0081] The filter box
303 further comprises a filtering element, such as for example a filtering mesh (not
shown in the figures for simplicity).
[0082] The filtering mesh is preferably substantially rectangular in shape and is sized
with a length and a height substantially equal to a length and a height of the second
transversal sidewall
303d.
[0083] Preferably, the filtering mesh is coupled with the second transversal sidewall
303d covering the apertures of the filtering windows
318a in such a way to filter the drying airflow passing therethrough (as will be described
in greater detail in the following).
[0084] The filtering mesh is preferably coupled with the second transversal sidewall
303d on an internal face thereof (i.e., facing the inside of the filter box
303).
[0085] The filtering mesh may be made in any suitable material, such as for example a suitable
polymer (e.g., Polyethersulfone or "PES") that may be over-injected onto the internal
face of the second transversal sidewall
303d.
[0086] Alternatively, the filtering mesh may be attached to the frame
318 of the second transversal sidewall
303d in any other suitable manner (e.g., by gluing together the filtering mesh and the
second transversal sidewall
303d) or, conversely, may be removably coupled with the frame
318 (e.g., by providing suitable snap-fit engage elements). Alternatively, a plurality
of smaller filtering meshes may be provided each one adapted to be coupled with a
respective filtering window
318a.
[0087] It should be noted that the mullion elements
318b, along enhancing the structural strength of the frame
318 also enhance a robustness of the filtering mesh preventing deformation of the filtering
mesh that the airflow may provoke, e.g. a bending of the central portion of the filtering
mesh in the direction of the flow of air that could cause a concentration of trapped
fluff in such bent central portion.
[0088] The filter box
303 preferably also comprises a cover support
324 attached to (or, alternatively, formed integral with) the front sidewall
303b.
[0089] The cover support
324 is designed to protrude outwards from the aperture
219 in the larger sidewall
217b in order to support the de-fluff filter cover
140.
[0090] For example, the de-fluff filter cover
140 may be coupled with the cover support
324 by means of one or more snap-fit elements (not shown), each fitting a corresponding
coupling element, such as holes
324a, provided on the cover support element
324.
[0091] Preferably, the cover support
324 comprises a tab 327 protruding substantially transversal to the front sidewall
303b and extending towards the rear sidewall
303a on an end of the cover support
324.
[0092] In other embodiments according to the present invention, a tab may be placed in a
different position and/or more than just a tab may be provided.
[0093] The tab
327 is advantageously provided in order to prevent incorrect insertions of the de-fluff
filter
218 into the filter housing
217.
[0094] For example, the de-fluff filter
218 is designed to inserted in the filter housing
217 only if the tab
327 is inserted inside a tab slot
230 (visible in
Figure 2B) that is provided on the separating wall
205a of the base element
205, which substantially separates the control panel
130 from the inner portion of the top
125, preferably in a position close to the aperture
219.
[0095] In different embodiments of the present invention, the cover support
324, the front sidewall
303b and/or the de-fluff filter cover
140 may be either formed as different elements that can be engaged one another in any
suitable known manner, or as a one-piece element.
[0096] In alternative embodiments of the present invention, an alternative cover element
may be provided featuring a grasping element (such as for example a handle).
[0097] The rear sidewall
303a of the filter box
303 comprises an inlet aperture
330 which is adapted to receive the drying airflow coming from the laundry treatment
chamber
105 through the inlet opening
210 in the shorter sidewall
217a.
[0098] Preferably the outlet portion, i.e. the second transversal sidewall 303d, has a greater
extension than the inlet aperture
330, such that the filtering mesh arranged on the outlet portion
303d may have a wide extension.
[0099] Preferably, the rear sidewall
303a is also provided with a protruding frame
333 that surrounds the inlet aperture
330 and protrudes from a border of the filter box
303 surrounding the inlet aperture
330 towards the outside of the filter box
303. The protruding frame
333 is adapted to engage with the gasket element
212a of the adapter element
212 preferably in an airtight manner (thus fluidly connecting the de-fluff filter
218 with inlet opening
210).
[0100] Advantageously, the swinging bulkhead
309 is provided at the inlet aperture
330. The swinging bulkhead
309 has a shape, e.g. substantially rectangular, adapted to close, preferably seal, the
inlet aperture
330. The swinging bulkhead
309 is designed to have a weight such that a kinetic force of the drying airflow from
the laundry treatment chamber
105 is able to swing the bulkhead towards the inside of the filter box
303 (thus, clearing the inlet aperture
330). The swinging bulkhead
309 may be made in any suitable material, e.g. a polymer.
[0101] Preferably, the swinging bulkhead
309 is hinged to the first transversal sidewall
303c and to the second transversal sidewall
303d close to the rear sidewall
303a. For example, the swinging bulkhead
309 may be provided with two protruding pins
309a on opposite shortest sides (at top corners thereof), which are adapted to be inserted
into two matching rear bores
336, a first one provided in the first transversal sidewall
303c and a second one provided in the second transversal sidewall
303d.
[0102] Preferably, at the inlet aperture
330 an abutment element (not shown) is provided. Advantageously, the abutment element
is adapted to prevent the swinging bulkhead
309 from swinging towards the outside of the filter box
303 (i.e., the swinging bulkhead
309 is allowed to swing only towards the inside of the filter box
303).
[0103] Thanks to the swinging bulkhead
309 and the abutment element it is possible to prevent, or substantially reducing, any
spurious flow of air from the de-fluff filter
218 towards the inlet opening
210 (i.e., opposite to the direction desired for the flow of drying air).
[0104] Preferably, in the bottom wall
303e a niche
339 is formed (as can be seen in the
Figure 3D). The niche
339 is adapted to operatively house a blocking/ejecting device (not shown in the drawings)
that allows both (mechanincally) blocking and ejecting the de-fluff filter
218 from its housing
217.
[0105] Advantageously, thanks to the blocking/ejecting device a user can easily unlock the
de-fluff filter
218 from its housing
217 simply by pressing the pushbutton portion
145 of the aesthetic cover
140 of the de-fluff filter
218.
[0106] Even more preferably, the blocking/ejecting device allows the de-fluff filter
218 to be at least slightly ejected from the filter housing
217 so as to be easily grasped by a user.
[0107] In an inner portion of the filter box
303 a guiding wall
354 may be preferably provided in order to guide the drying airflow from the inlet aperture
330 to the second transversal sidewall
303d.
[0108] For example, the guiding wall
354 may be a curved wall connecting the first transversal sidewall
303c with an end of the second transversal sidewall
303d adjacent to the front sidewall
303b.
[0109] Generally, the guiding wall
354 is designed in such a way to provide the best fluid-dynamic behaviour for the drying
airflow inside the filter box
303 (e.g., adapted to effectively direct the drying airflow homogenously towards the
whole second transversal sidewall
303d generating the lowest turbulence in the drying airflow as possible).
[0110] Even more preferably, the guiding wall
354 may comprise a bent (or slanted) portion
354a at the intersection with the bottom wall
303e of the filter box 303. The bent portion
354a of the guiding wall
354 is designed for provide the best fluid-dynamic behaviour for the drying airflow inside
the filter box
303 (as generally the whole the guiding wall
354) and also avoids fluff stockpiling facilitated by sharp angles (e.g., substantially
at 90°) at the intersection between the guiding wall
354 and the bottom wall
303e.
[0111] The top aperture
303t of the filter box
303 is closed by the lid
306, preferably in an airtight manner. The lid
306 may be preferably made of a suitable polymer.
[0112] More preferably the lid
306 is made of a bi-component plastic using over-injection technology. For example, a
lid frame
357, preferably comprising peripheral portion
357a and internal (reinforcing) ribs
357b, may be made of Acrylonitrile Butadiene Styrene (ABS). Conversely, transparent panes
360 provided enclosed by the lid frame
357, preferably with each transparent pane
360 provided in position delimited by ribs
357b and/or the peripheral portion
357a of the lid frame
357, may be made of Polycarbonate (PC). The transparent panes
360 allow a user to verify the presence, and the quantity, of fluff trapped inside the
filter box 303 without the need of opening it.
[0113] As can be best appreciated from Figures 4A to 4C, on the lid frame 357, a sealing
border 357c is preferably provided.
[0114] The sealing border 357c protrudes from the lid frame 357 from a lower side thereof
(i.e., towards the inside of the filter box 303 when the lid 306 closes the top aperture
303t of the latter), and preferably along positions of the lid frame 357 that corresponds
to the rear sidewall
303a, the second transversal sidewall
303d, the guiding wall
354 and a portion of the first transversal sidewall
303c of the filter box
303.
[0115] For example, the sealing border
357c comprises a plurality of lid ridges
363 protruding downwards (i.e., towards the filter box
303 once the lid
306 is coupled therewith).
[0116] Correspondingly, on a topmost portion of the rear sidewall
303a, the second transversal sidewall
303d, the guiding wall
354 and a portion of the first transversal sidewall
303c of the filter box
303 corresponding box ridges
367. The box ridges
367 protrude upwards (i.e., towards the lid
306 once the filter box
303 is coupled therewith).
[0117] The lid ridges
363 and the box ridges
367 are arranged for intersperse once the lid
306 is coupled with the filter box
303t in the closed position.
[0118] Thanks to the lid ridges
363 and the box ridges
367, the sealing border
357c and the top portion of the sidewalls
303a,
303c, and
303d are adapted to hinder the passage to fluff by forming a meandering path (or 'maze'
as can be appreciated in
Figures 4A to
4C).
[0119] In summary, the sealing border
357c is designed to substantially seal the top aperture
303t of the filter box
303, when the lid
306 is in a closed position, thus allowing air entering and/or exiting a hollow chamber
361 within the de-fluff filter
218 (i.e., defined by the filter box
303 and the lid
306 in closed position in which trapped fluff remains confined) only through the inlet
aperture
330 and the filtering windows
318a in the second transversal sidewall
303d.
[0120] In an embodiment of the invention, the sealing border
357c and the top portion of the sidewalls
303a,
303c, and
303d may be designed in such a way to couple together by substantially a snap-fit engagement.
[0121] In a further embodiment of the present invention, as an alternative or an addition,
the sealing border
357c may also be provided with a gasket and/or the lid ridges
363 and the box ridges
367 may be formed in a resilient material (e.g., a rubber-like material which may be,
e.g., overmoulded on the material of the filter box
303) in order to obtain an improved airtight coupling with the filter box
303.
[0122] In order to allow a user easily opening (i.e., de-couple) the lid
306 from the filter box
303, one or more grasping portions may be provided, such as for example one or more opening
flaps
357d, preferably at ends of the peripheral portion
357a of the lid frame
357 corresponding to the first transversal sidewall
303c and the second transversal sidewall
303d in the proximity of the rear sidewall
303a of the filter box
303.
[0123] In order to be pivotally coupled with the filter box
303, the lid
306 comprises a couple of hinges
366, preferably protruding substantially at opposite ends of a front side of the lid
306 (i.e., corresponding to the front sidewall
303b of the filter box
303).
[0124] Each hinge
366 protrudes from the lid frame
357 transversally thereto and has a pin
366a in its turn protruding from the center of a flat portion
366b transversally thereto, with the flat portion
366b that is preferably substantially circular.
[0125] Each pin
366a is adapted to engage a matching front bore
369 provided on the first transversal sidewall
303c and on the second transversal sidewall
303d in a location adjacent to the front sidewall
303b.
[0126] According to the present invention, the de-fluff filter
218 further comprises an airflow diverter.
[0127] The airflow diverter is arranged to divert, at least partly, the flow of air within
the hollow chamber
361 defined within the filter box
303 closed by the lid
306 during the laundry machine
100 operation.
[0128] Even more preferably, the airflow diverter is arranged for dynamically diverting
the airflow within the filter box
218.
[0129] According to the invention, the airflow diverter is arranged for diverting the airflow
within the filter box
218 according to a quantity of fluff trapped therein.
[0130] According to an embodiment of the invention, the airflow diverter comprises a septum
370, which is adapted to be coupled with the filter box
218.
[0131] Preferably, the septum
370 is designed to be coupled with the filter box
303, as can be seen in Figures
3B, 3D and
4A.
[0132] The septum
370, as can be appreciated in
Figures 5A and
5B (which are a side view and a top view thereof, respectively), has substantially a
rectangular shape.
[0133] The septum
370 comprises a peripheral frame
370a that defines a plurality (e.g., five in the example of the figures) of septum filtering
windows
370b together with corresponding separating elements, such as for example (septum) mullion
elements
370c, which separate each septum filtering window
370b from adjacent septum filtering windows
370b.
[0134] Preferably, the septum mullion elements
370c are integral with the peripheral frame
370a.
[0135] In one embodiment of the invention, the structure formed by the peripheral frame
370a and the mullion elements
370c comprises two halves, i.e. a first structure half
375a and a second structure half
375b.
[0136] Preferably, each structure halves
375a and
375b are symmetrical one to the other, and each structure half
375a and
375b defines a respective side of the septum
370.
[0137] For example, a first side of each structure half
375a and
375b defines a lateral side of the septum
370 and a second side is designed to couple (e.g., by snap-fit, bayonet mounting, through
the use of fastening/clamping means,
etc.) with a second side of the other structure half
375b or
375a. In other words, the structure halves
375a and
375b couple one with the other along a longitudinal symmetry plane
VI of the septum
370.
[0138] The septum
370 further comprises a filtering element, such as for example a septum filtering mesh
(not shown in the figures for simplicity).
[0139] The septum filtering mesh is preferably substantially rectangular in shape and is
sized with a length and a height substantially equal to a length and a height of the
septum
370.
[0140] Preferably, the septum filtering mesh is coupled with the peripheral frame
370a and the mullion elements
370c in order to being exposed at the septum filtering windows
370b.
[0141] For example, the filtering mesh is suited to be inserted between the structure halves
375a and
375b of the septum 370 and being maintained in a working position once the structure halves
375a and
375b are coupled together.
[0142] The septum
370 further comprises feet elements
380a and
380b arranged for coupling with the filter box
300 and maintaining the septum
370 in a working position within the de-fluff filter
218.
[0143] In one embodiment of the invention, each foot element
380a and
380b comprises a disc element protruding from the peripheral frame
370a and transversally therethrough (e.g., with each structure half
375b or
375a comprising a half of the disc).
[0144] Preferably, each foot element
380a and
380b is provided in correspondence of a respective mullion element
370c of the septum
370.
[0145] The feet elements
380a and
380b are arranged for coupling with corresponding feet receptacles
385a and
385b provided in the bottom wall
303e.
[0146] For example, each foot receptacle
385a and
385b may comprise a discoidal dent adapted to receive a foot element
380a and
380b. In an embodiment of the invention a diameter of the feet receptacles
385a and
385b is slightly smaller than a diameter of the feet elements
380a and
380b in order to provide an interference fitting of the feet receptacles
385a and
385b with the feet elements
380a and
380b.
[0147] In alternative or in addition, as can be appreciated in
Figure 4A each foot receptacle
385a and
385b may comprise a peg element
405 protruding from the bottom wall
303e of the filter box
303. Correspondingly, each foot element
380a and
380b comprises a peg receptacle
410 arranged for receiving the peg element
405.
[0148] In one embodiment of the invention, the peg element
405 is arranged for snap-fitting with the peg receptacle
410.
[0149] Preferably, a pair of (terminal) retaining brackets
390a and
390b in the filter box
303 for maintaining the septum
370 in its working position.
[0150] In one embodiment of the invention, the retaining brackets
390a and
390b protrude from the bottom wall
303e of the filter box
303 towards the top aperture
303t.
[0151] Each retaining bracket
390a is preferably arranged for removably receiving a free end of the septum
370 in such a way to prevent excessive oscillations thereof during the operation of the
laundry machine
100.
[0152] For example, the retaining brackets
390a and
390b has substantially a "C" shaped in top view defining respective concave spaces that
are suited for receiving the opposite ends of the septum
370.
[0153] Preferably, the septum
370 is coupled with the filter box
303 by inserting the opposite ends of the septum
370 in concave spaces of the retaining brackets
390a and
390b and pushing the septum
370 towards the bottom wall
303e of the filter box
303 until the feet elements
380a and
380b engage with the feet receptacles
385a and
385b.
[0154] Once the septum
370 is in its working position inside the filter box
303 the inner space delimited by the filter box
303 (and thus also the hollow chamber
361 defined within the filter box
303 closed by the lid
306) results substantially subdivided in two different regions
395a and
395b.
[0155] Preferably, the septum
370 is designed for substantially being flush with the bottom wall
303e of the filter box
303 and for reaching the lid
306, preferably contacting the latter, once the lid
306 is in its closed position (as can be appreciated in
Figure 4A).
[0156] According to the invention, during operation of the laundry machine
100, the septum
370 is arranged for diverting the flow of air from a first region
395a to a second region
395b of the two different regions
395a and
395b. The septum
370 is arranged for diverting the flow of air from the first region
395a to the second region
395b in a substantially automatic manner. The septum
370 diverts the airflow from the first region
395a to the second region
395b trigger by an amount of fluff collected within the hollow chamber
361 of the de-fluff filter
218 during the operation thereof.
[0157] In the exemplary embodiment at issue, initially the airflow carrying moisture and
fluff accessing the hollow chamber
361 of the de-fluff filter
218 through the inlet aperture
330 and is mainly driven into the first region
395a by the shape of the hollow chamber
361 (thanks to the shape of the guiding wall
354) of the de-fluff filter
218.
[0158] Preferably, the septum
370 is arranged inside the hollow chamber
361 of the de-fluff filter
218 in such a way to define, together with the guiding sidewall
354, the first region
395a having a decreasing transversal section along the direction defined by the flow of
air (i.e., substantially from the inlet aperture
330 towards the front sidewall
303b).
[0159] In other words, the septum
370 together with the de-fluff filter
218 defines a path having at least one convergent portion along the direction of the
flow of air. Advantageously, flow of air is guided towards an end of the first region
395a, i.e. at the intersection between the septum
370 and the guiding wall
354, and then crosses the septum filtering windows
370b.Therefore, substantially the whole (or a majority of the) airflow crossing the de-fluff
filter
218 is initially filtered by the septum filtering windows
370b of the septum
370. Accordingly, the fluff is substantially mainly confined in the first region
395a, while the airflows reaches second region
395b beyond the septum
370 and the leaves the hollow chamber
361 of the de-fluff filter
218 through the second transversal sidewall
303d.
[0160] During the proceeding of the operation of the laundry machine
100 fluff accumulates more and more in the first region
395a and, accordingly, a flow rate through the septum filtering windows
370b of the septum
370 progressively reduces.
[0161] In the considered embodiment, the reduction of the flow rate through the septum filtering
windows
370b is due to accumulation of fluff at the septum filtering windows
370b of the septum
370 pushed by the airflow thereagainst.
[0162] Therefore, the airflow entering the hollow chamber
361 of the de-fluff filter
218 is progressively diverted from the first region
395a to the second region
395b as the flow rate through the septum filtering windows
370b of the septum
370 progressively drops.
[0163] The accumulation of fluff at the septum filtering windows
370b of the septum
370 may reduce the flow rate through the septum
370 to the point that substantially all the airflow is diverted from the first region
395a to the second region
395b of the hollow chamber
361.
[0164] It should be noted that a threshold amount of fluff that provokes the diversion of
the airflow is a function of the size of the de-fluff filter
218, of the first region
395a of the hollow chamber
361, of the septum
370 and of the septum filtering windows
318a.
[0165] The fluff in the airflow diverted for entering directly in the second region
395b is filtered by the septum filtering windows
318a of the second transversal sidewall
303d before exiting the de-fluff filter
218.
[0166] It should be noted that the filtering windows
318a are substantially free of fluff at this point of the drying process and thus ensure
an unreduced flow rate of the airflow therethrough.
[0167] For example, in an initial phase of the laundry machine
100 operation the flow of air is mainly filtered by the septum filtering window
370b closer to the guiding wall
354 (i.e., the farthest from the inlet aperture
330) which, as the process the laundry machine
100 operation, is firstly clogged by fluff filtered from the flow of air crossing the
septum
370.
[0168] The flow of air is progressively diverted from the septum filtering window
370b closer to the guiding wall
354 to the septum filtering window
370b adjacent thereto, and so on until all the septum filtering windows
370b are substantially clogged (i.e., the flowrate of air flowing through each septum
filtering window
370b is substantially reduced by the trapped fluff).
[0169] Once all the septum filtering windows
370b of the septum
370 are substantially clogged causes the air flow to be diverted to the second region
395b of the hollow chamber
361 where the unclogged filtering windows
318a of the second transversal sidewall
303d ensure an higher flowrate.
[0170] In other words, the septum
370 divides the hollow chamber
361 in two regions, i.e. the first region
395a and the second region
395b, which define, for the flow of drying air, two paths causing a different amount of
pressure drops, and accordingly energy losses (e.g., due to friction), to the portions
of fluid (e.g. moisture and fluff-laden air) travelling through the first region
395a and the second region
395b.
[0171] Preferably, the flow of air inside the de-fluff filter
218 follows a path through the first region
395a or through the second region
395b of the hollow chamber 361 which currently offers the lowest pressure drop, or the
lowest energy losses. Particularly, initially the amount of energy losses caused by
the first portion
395a of the hollow chamber
361 to the airflow is lower than the amount of energy losses caused by the second portion
395b thereto in an initial phase of the laundry machine
100 operation (i.e., when the septum filtering windows
370b are unclogged).
[0172] Successively, as the septum filtering windows
370b progressively clog, the energy losses along a path of the flow of air through the
first region
395a of the hollow chamber start to rise until a path for the flow of air through the
second region
395b result to provoke lower energy losses to the airflow than the path of the flow of
air through the first region
395a.
[0173] Thanks to the septum
370 of the de-fluff filter
218 according to an embodiment of the present invention, a flow rate of the airflow exiting
the de-fluff filter
218 remains substantially constant for longer periods during the operation of the laundry
machine
100 even in the occurrence of large amounts of fluff collected in the de-fluff filter
218, as can be appreciated in
Figure 6 that is a chart showing air pressure as a function of time during operation of the
laundry machine
100 according to an embodiment of the invention and of a laundry machine known in the
art.
[0174] In detail, a first air-pressure curve
605 is a measurement of the air pressure (measured in mmH
2O) as a function of time during operation of a laundry machine
100 comprising the de-fluff filter
218 according to an embodiment of the present invention and a second air-pressure curve
610 is a measurement of air pressure as a function of time during the operation of a
laundry machine known in the art.
[0175] It should be noted that the first air-pressure curve
605 remains substantially constant for a longer extent of time than the second air-pressure
curve
610. Moreover, the rise in pressure exhibited by the first air-pressure curve
605 is substantially linear and with a very low angular coefficient, while the rise in
pressure exhibited by the second air-pressure curve
610 result to be steeper with a non-linear trend and reaches a maximum value (at the
end of the operation) substantially higher than the maximum value reached by the first
air-pressure curve
605.
[0176] This ensures a more stable air pressure in the whole air circuit of the laundry machine
100 that entails high efficiency of the laundry machine operation.
[0177] Thanks to the substantially stable pressure during the operation of the laundry machine
100 ensured by the de-fluff filter
218 according to embodiments of the present invention lead to a substantially homogeneous
operation of the heat pump of the air circuit of the laundry machine
100.
[0178] For example, a compressor (not shown) comprised in the heat pump may operate with
a substantial constant number of round per minute, or with a limited variations of
rounds per minute.
[0179] Moreover, a capillary temperature results to be lower during the operation of the
laundry machine
100 as can be appreciated in
Figure 7 that is a chart showing capillary temperature as a function of time during the operation
of a laundry machine
100 according to an embodiment of the invention and of a laundry machine known in the
art.
[0180] In detail, a first temperature curve
705 is a measurement of temperature (measured in Celsius degrees) as a function of time
during operation of a laundry machine
100 comprising the de-fluff filter
218 according to an embodiment of the present invention and a second temperature curve
610 is a measurement of temperature as a function of time during the operation of a laundry
machine known in the art.
[0181] It should be noted that the first temperature curve
705 remains equal to or lower than the second temperature curve
710 during the whole considered time. In addition, the first temperature curve
705, apart for limited variations, remains substantially constant once reached a steady
value of temperature during the operation of the laundry machine
100, while the second curve
710 exhibits a substantially linear increase in temperature during the operation of the
laundry machine after an initial steep increase.
[0182] In other embodiments of the invention (not shown), different airflow diverters may
be implemented.
[0183] For example, airflow diverters may be arranged for automatically swinging from a
first position, in which the airflow is directed into a first portion of the de-fluff
filter, to a second position, in which the airflow is directed into a second portion
of the de-fluff filter, according to a quantity of fluff currently trapped in the
de-fluff filter. The airflow diverter could be hinged to the bottom wall of the filter
box in such a way to swing from the first position to the second position as above
described. The movement of such diverters being caused by the airflow itself or by
a driving device.
[0184] Alternatively, a deformable airflow diverter (e.g., manufactured in a resilient material)
may be arranged for having a rest configuration, in which the airflow is directed
into a first portion of the de-fluff filter, and is arranged for shift to a deformed
configuration, in which the airflow is directed into a second portion of the de-fluff
filter, according to a quantity of fluff currently trapped in the de-fluff filter.
The deformation of such diverter being caused by the airflow itself or by a deformation
inducing device.
[0185] It should be noted that the laundry machine
100 may operate also without the auxiliary de-fluff filter
221 and/or the septum
370 in their working positions, i.e. with only the filtering mesh of the second transversal
sidewall
303d of the de-fluff filter
218 filtering the airflow coming from the laundry treatment chamber
105.
[0186] Indeed, in alternative embodiments of the present invention, the auxiliary filter
221 and its housing may be omitted.