AU2017202723B2

AU2017202723B2 - Laundry treating machine comprising a removable de-fluff filter

Info

Publication number: AU2017202723B2
Application number: AU2017202723A
Authority: AU
Inventors: Francesco Cavarretta; Roberto Mazzocco; Marco Rizzi
Original assignee: Electrolux Appliances AB
Current assignee: Electrolux Appliances AB
Priority date: 2016-05-17
Filing date: 2017-04-26
Publication date: 2023-03-02
Anticipated expiration: 2037-04-26
Also published as: EP3246455B1; PL3246455T3; AU2017202723A1; EP3246455A1

Abstract

EP/FC-MM P-61639/EP 32 ABSTRACT LAUNDRY TREATING MACHINE COMPRISING A REMOVABLE DE-FLUFF FILTER 5 A laundry machine (100) adapted to dry laundry by means of a flow of drying air is proposed. The laundry machine comprises: a casing (110); inside the casing, a laundry treating chamber (105) adapted to contain the laundry to be dried; an air circuit in fluid communication with the laundry treating chamber through an inlet 10 opening (210) and through an outlet opening (215), and defining an air-path for the flow of drying air between said inlet (210) and outlet (215) openings; a filter housing (217) for removably accommodating a de-fluff filter (218), said filter housing (217) being provided in the air-path and being accessible through a housing aperture (219). The de-fluff filter (218) is arranged for trapping fluff or lint particles carried by the 15 flow of drying air crossing said de-fluff filter (218), the de-fluff filter (218) comprises a filtering element (318) and a hollow chamber (361) which comprises an inlet aperture (330) and an outlet portion (303d). The de-fluff filter (218) further comprises an airflow diverter (370) which: divides the hollow chamber (361) of the de-fluff filter (218) in a first portion (395a) and a second portion (395b), and diverts 20 the flow of drying air entering the de-fluff filter (218) towards the first portion (395a) of the hollow chamber (361) or towards the second portion (395b) of the hollow chamber (361) according to an amount of fluff currently trapped in the de-fluff filter (218). (FIG.3B) 5/13 Cf) 0 Cf) CD m Cf) ce) Cf) 0 co ce) V ce) 0 ce) ce) co 0 V Cf) Cf) cu ce) 00 0 T- co CO m 00 0 cr) ce) ce) co C) V co m Cf) 0 (,D C ) -0 00 0 00 V ce) V CD COM ce) 00 C) V rl- ce) ce) C) 00 co ce) Cf) 0 CD co ce) r- V- ce) coo ce) 0 [1- 00 ce) ce) m L) 00 m CD LO I m m ce) co 00 co 0 co m 1- 00 Cf) co IT 0 LO co co CO ce) V 0 Cr6 0 00 co m co CD ce) co 0 m ce) cr) ce) ce) 0 ce) C14 CD C14 ce) CO ce) C14 N co co ce) V CN IT CN CV)

Description

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115173-EP/FC-MM P-61639/EP

1

LAUNDRY TREATING MACHINE COMPRISING A REMOVABLE DE-FLUFF FILTER

Field of the invention 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

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.

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.

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.

Once in the air circuit, the fluff is likely to accumulate therein, thereby

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2

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. 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.

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.

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.

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

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. 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. 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 afirst 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 de-flufffilter. In an embodiment of 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. Preferably, 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. In an embodiment of the invention, 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. 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. 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. 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. 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. 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 afiltering element provided in the airflow diverter or in the de-fluff filter. 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. In an embodiment of the invention, the peripheral frame is integral with the at least one separating element. 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. In an embodiment of the invention, the airflow diverter is removably mounted in the hollow chamber of the de-fluff filter. In an embodiment of the invention, the airflow diverter further comprises at least one foot element arranged for coupling with the de-fluff. 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. 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. In an embodiment of the invention, the de-fluff filter further comprises a filter box and a lid hinged to thefilter 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. 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. 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. 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. 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. According to another example aspect of the invention, there is provided a laundry machine adapted to dry laundry by means of a flow of drying air. 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 through an outlet opening, and defining an air-path for the flow of drying air between said inlet and outlet openings; and 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 comprising a first filtering element and a hollow chamber which comprises an inlet aperture and an outlet portion, wherein the first filtering element is arranged on the outlet portion. The de-fluff filter further comprises an airflow diverter which is adapted to divide the hollow chamber of the de fluff filter into a first portion and a second portion. The airflow diverter comprises at least one second 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. The airflow diverter is adapted to divert 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 second filtering element, wherein airflow entering the hollow chamber of the de-fluff filter is progressively diverted from the first portion to the second portion as the flow rate through the at least one secondfiltering element progressively drops due to accumulation of fluff at the least one secondfiltering element.

6A

Brief description of the annexed drawings 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-flufffilter according to an embodiment of the present invention; Figure 3B is a perspective view of a de-flufffilter 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 HID 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;

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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 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.

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.

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.

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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.

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).

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.

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). 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.

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.

In the region of the base element 205, preferably near the front-left corner

thereof, a filter housing 217 is provided. The filter housing 217 is suitable to house a de-fluff filter 218 (described in

greater detail below). 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

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housing aperture 219 opened on the machine front wall 115 preferably in a

separating wall 205a of the base element 205.

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. 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). 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).

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.

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).

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. 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.

In one embodiment of the present invention, the transversal opened side 217d

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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.

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.

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.

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.

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.

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.

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. 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.

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

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heater instead of the heat pump apparatus.

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.

The top 125 is completed by an outer (aesthetic) panel 240. 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.

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).

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. 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.

After exiting the drum through the chamber outlet, the flow of now moisture-

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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. 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).

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. 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.

It should be noted that the de-fluff filter 218 is shown with also the aesthetic cover 140 removed in the following figures.

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.

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). 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

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PP).

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.

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). 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.

The filter box 303 further comprises a filtering element, such as for example a

filtering mesh (not shown in the figures for simplicity).

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

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transversal sidewall 303d.

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). 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). 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. 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.

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.

The filter box 303 preferably also comprises a cover support 324 attached to

(or, alternatively, formed integral with) the front sidewall 303b. 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. 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.

Preferably, the cover support 324 comprises a tab 327 protruding

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substantially transversal to the front sidewall 303b and extending towards the rear

sidewall 303a on an end of the cover support 324.

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.

The tab 327 is advantageously provided in order to prevent incorrect insertions of the de-fluff filter 218 into the filter housing 217.

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.

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. In alternative embodiments of the present invention, an alternative cover

element may be provided featuring a grasping element (such as for example a

handle). 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.

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.

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).

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16

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. 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. 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). 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). 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.

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.

115173-EP/FC-MM P-61639/EP

17

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.

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.

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.

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).

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.

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. 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

115173-EP/FC-MM P-61639/EP

18

presence, and the quantity, of fluff trapped inside the filter box 303 without the need

of opening it.

As can be best appreciated from Figures 4A to 4C, on the lid frame 357, a

sealing border 357c is preferably provided.

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. 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).

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).

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.

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).

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.

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19

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.

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.

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. 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). 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.

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.

In an embodiment of the present invention, the de-fluff filter 218 further comprises an airflow diverter.

Preferably, 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.

Even more preferably, the airflow diverter is arranged for dynamically

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20

diverting the airflow within the filter box 218.

In an embodiment of the invention, the airflow diverter is arranged for

diverting the airflow within the filter box 218 according to a quantity of fluff trapped

therein.

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.

Preferably, the septum 370 is designed to be coupled with the filter box 303, as can be seen in Figures 3B, 3D and 4A.

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. 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. Preferably, the septum mullion elements 370c are integral with the peripheral

frame 370a.

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.

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. 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.

The septum 370 further comprises a filtering element, such as for example a

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21

septum filtering mesh (not shown in the figures for simplicity).

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.

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. 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. 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.

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). Preferably, each foot element 380a and 380b is provided in correspondence

of a respective mullion element 370c of the septum 370.

The feet elements 380a and 380b are arranged for coupling with

corresponding feet receptacles 385a and 385b provided in the bottom wall 303e.

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.

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.

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22

In one embodiment of the invention, the peg element 405 is arranged for

snap-fitting with the peg receptacle 410.

Preferably, a pair of (terminal) retaining brackets 390a and 390b in the filter

box 303 for maintaining the septum 370 in its working position.

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. 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. 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.

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. 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.

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).

According to an embodiment of 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.

Preferably, the septum 370 is arranged for diverting the flow of air from the

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23

first region 395a to the second region 395b in a substantially automatic manner.

More preferably, 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.

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.

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). 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.

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.

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.

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24

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.

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.

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. 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. 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.

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. 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).

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

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25

the hollow chamber 361 where the unclogged filtering windows 318a of the second

transversal sidewall 303d ensure an higher flowrate.

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.

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). 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.

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.

In detail, a first air-pressure curve 605 is a measurement of the air pressure

(measured in mmH20) 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

115173-EP/FC-MM P-61639/EP

26

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.

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.

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.

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. 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.

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. 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.

It should be noted that the first temperature curve 705 remains equal to or

115173-EP/FC-MM P-61639/EP

27

lower than the second temperature curve710 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.

In other embodiments of the invention (not shown), different airflow diverters may be implemented.

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.

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. 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.

Indeed, in alternative embodiments of the present invention, the auxiliary

filter 221 and its housing may be omitted.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as, an acknowledgement or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

Claims

The claims defining the invention are as follows:

1. A laundry machine adapted to dry laundry by means of a flow of drying air, the laundry machine comprising: 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 through an outlet opening, and defining an air-path for the flow of drying air between said inlet and outlet openings; and 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 being arranged for trapping fluff or lint particles carried by the flow of drying air crossing said de-fluff filter, the de-fluff filter comprising a first filtering element and a hollow chamber which comprises an inlet aperture and an outlet portion, wherein the first filtering element is arranged on the outlet portion; wherein the de-fluff filter further comprises an airflow diverter which is adapted to divide the hollow chamber of the de-fluff filter into a first portion and a second portion; wherein the airflow diverter comprises at least one second 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; and wherein the airflow diverter is adapted to divert 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 second filtering element, wherein airflow entering the hollow chamber of the de-fluff filter is progressively diverted from the first portion to the second portion as the flow rate through the at least one second filtering element progressively drops due to accumulation of fluff at the least one secondfiltering element.

2. The laundry machine according to claim 1, wherein the hollow chamber of the de-fluff filter is shaped to direct the majority of drying air flow entering the de-fluff filter to the first portion of the hollow chamber in a first part of a drying process when the at least one second filtering element is free of fluff, and to ensure an unreduced flow rate of the airflow therethrough.

3. The laundry machine according to claim 1 or 2, wherein 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.

4. The laundry machine according to claim 3, wherein the amount of energy losses caused by the first portion is lower than the amount of energy losses caused by the second portion in an initial phase of the laundry machine operation.

5. The laundry machine according to claim 3 or 4, wherein, during a laundry drying process, the progressive accumulation of fluff or lint particles in the first portion 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.

6. The laundry machine according to claim 5, wherein 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 portion to the second portion of the hollow chamber.

7. The laundry machine according to claim 6, wherein said threshold amount of fluff or lint particles is a function of at least one of: a size of the first portion, 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.

8. The laundry machine according to any one of claims I to 7, wherein the airflow diverter is removably mounted in the hollow chamber of the de-flufffilter.

9. The laundry machine according to any one of claims 1 to 8, wherein the de fluff filter further comprises one or more retaining brackets for holding the airflow diverter in a working position within the hollow chamber.

10. The laundry machine according to any one of claims 1 to 9, wherein the de fluff filter further comprises a filter box and a lid hinged to thefilter box, wherein the lid is pivotable from an open 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, and wherein 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.

11. The laundry machine according to claim 10, wherein the lid comprises a plurality of lid ridges protruding towards the filter box when the lid is in the closed position, and wherein the filter box comprises corresponding box ridges protruding towards the lid when the lid is in the closed position, the lid ridges being arranged for interspersing with the box ridges when the lid is in the closed position thereby forming a meandering path capable of hindering the passage of fluff.

12. The laundry machine according to any one of claims 1 to 11, wherein 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.

13. The laundry machine according to any one of claims 1 to 12, wherein the airflow diverter is movable from a first position, in which the airflow is directed into the first portion of the hollow chamber, to a second position, in which the airflow is directed into the second portion of the hollow chamber.

14. The laundry machine according to any one of claims 1 to 13, wherein the airflow diverter is deformable between a rest configuration, in which the airflow is directed into the first portion of the hollow chamber, and a deformed configuration, in which the airflow is directed into the second portion of the hollow chamber.