WO2014080328A1

WO2014080328A1 - Method and household appliance for drying laundry

Info

Publication number: WO2014080328A1
Application number: PCT/IB2013/060166
Authority: WO
Inventors: Nicola Colucci; Lorenzo Verdini; Sandro Duri
Original assignee: Indesit Company S.P.A.
Priority date: 2012-11-22
Filing date: 2013-11-15
Publication date: 2014-05-30
Also published as: ITPR20120080A1

Abstract

A method for drying laundry by means of a household appliance (1 ) comprising an outer shell (5) that contains delimiting means (34) for delimiting an inner laundry drying compartment (3), the compartment (3), in turn, containing a rotating drum (4) for holding the laundry. The method comprises a stage that determines a condensation of at least part of the moisture present in the compartment (3) on at least a portion of the delimiting means (34), said moisture being determined by the wet laundry placed in the drum (4). The stage that determines the condensation of the moisture, in turn, comprises the stages of: introducing a flow of air inside the shell (5), having it travel through at least one inlet opening (21 ) afforded in a front wall (51 ) of the outer shell (5); conveying the flow of air from the inlet opening (21 ) to at least one outlet opening (22) located in a rear or side wall (52, 53, 54) of the shell (5); the stage of conveying the air flow comprises the stage of the flow of air flowing against said delimiting means (34) so as to determine a cooling thereof; the stage of flowing against the delimiting means (34) provides that the air flow come into contact with the delimiting means (34) externally of the compartment (3), but internally of the shell (5); having said flow of air flow outside the shell (5), having it travel through at least said outlet opening (22).

Description

METHOD AND HOUSEHOLD APPLIANCE FOR DRYING LAUNDRY Technical field

The object of the present invention is a method and a household appliance for drying laundry.

Background Art

Known dryers are described in patent EP1688524. These dryers comprise a drying compartment, which, in turn, comprises a rotating drum. In combination with a plate located inside the drying compartment, an internal wall of the drying compartment identifies a hollow space in which a liquid coolant (water) can flow, determining condensation of the moisture created by the laundry placed in the drum. This then enables the drying process to begin directly in the drying compartment and not in a condenser located downstream.

One drawback of this structural solution is related to the operating and realization costs of the devices aimed at bringing about condensation of the moisture in the drying compartment.

In fact, the realization of the hollow space inside the drying compartment complicates the household appliance. The use of water as a coolant fluid also requires particular devices such as conduits, which must ensure maximum tightness.

Disclosure of the Invention

In this context, the aim of the present invention is to propose a method and a household appliance for drying laundry that makes it possible to minimize assembly costs.

The defined technical task and the specified aims are substantially achieved by a method and a household appliance for drying laundry having the technical characteristics stated in one or more of the appended claims.

Brief Description of the Drawings

Further characteristics and advantages of the present invention will become more apparent from the approximate, and thus non-limiting, description of a preferred, but not exclusive embodiment of a method and a household appliance for drying laundry according to the present invention and illustrated in the accompanying drawings, in which:

-Figures 1 and 2 are two perspective views of a household appliance according to the present invention, with some parts being omitted so as to illustrate others more clearly;

-Figure 3 shows a detail of a particular structural solution for a household appliance according to the present invention;

-Figure 4 is a schematic view of a household appliance according to the present invention.

Detailed Description of the Preferred Embodiments of the Invention

A household drying appliance is indicated by the reference number 1 in the attached figures. This household drying appliance 1 could be a dryer for example, but also a washer dryer (in this latter case, in addition to performing a drying action, it could also perform a washing action). The household appliance 1 comprises delimiting means 34 for delimiting a drying compartment 3; this delimiting means 34 defines what is called the tub in technical jargon. Therefore, the drying compartment 3 is the space inside the tub. The household appliance 1 further comprises a drum 4 for containing laundry and that can rotate. The drum 4 is located inside the drying compartment 3. The drum 4 normally has a plurality of holes so as to enable a fluid communication between the inside and the outside of the drum 4 (for passage of the hot air for drying the laundry during a drying cycle or for passage of the washing liquid during a possible washing cycle).

The household appliance 1 further comprises an outer shell 5 that houses the delimiting means 34 thereinside. Conveniently, the outer shell 5 is a case that is open at the bottom and that delimits the household appliance 1 externally. It also defines the aesthetic outer casing of the household appliance 1 .

The shell 5 comprises: -a front wall 51 and a rear wall 52 that are opposite one another;

-two side walls 53, 54 that are opposite one another and connecting the front wall 51 and the rear wall 52.

The front wall 51 is the wall that faces the user during normal use. A door 9 for access to said drum 4 is typically afforded in said front wall 51 . This front wall 51 extends from the bottom upwards (preferably vertically). Conveniently, the rear wall 52 also extends from the bottom upwards (typically it is vertical). Conveniently, the rear wall 52 is not usually visible to the user. It is substantially parallel to the front wall 51 . The two side walls 53, 54 involve a first and a second flank of the household appliance 1 , respectively.

The shell 5 typically also comprises an upper base 91 . In the preferred solution, the shell 5 does not comprise a bottom base, given that it is normally defined by a resting surface for the household appliance 1 . There is a distance of a few centimetres between the side walls 53, 54 and the resting surface, and between the front or rear wall 51 , 52 and the resting surface.

Conveniently, the shell 5 is substantially shaped like a parallelepiped having an open bottom base.

The household appliance 1 conveniently comprises ventilating means 6 for ventilating at least one surface of the delimiting means 34. This brings about the cooling of at least part of the delimiting means 34. In this manner, there is condensation of at least part of the moisture present in the compartment 3 and generated by the wet laundry located in the drum 4. The condensation involves a surface that delimits the compartment 3 and that is part of the delimiting means 34 (in other words, the condensate is deposited on an internal surface of the delimiting means 34).

The ventilating means 6 comprises an inlet opening 21 for air to enter the shell 5 and an outlet opening 22 for air to exit the shell 5. The inlet opening 21 is afforded in the front wall 51 of the household appliance 1 . The outlet opening 22 is afforded in the rear wall 52 or in at least one of said side walls of the shell 5. In the preferred solution, the outlet opening 22 is afforded in the rear wall 52, as in this manner, the air crosses through the entire household appliance 1 , thus flowing against the delimiting means 34 afforded therein. For similar reasons, the outlet opening 22 could be advantageously afforded in one of said side walls at a distance of less than 10 centimetres from the lower wall 52.

The shell 5 and the delimiting means 34 delimit an inner space 540 interposed therebetween that puts said inlet opening 21 and said outlet opening 22 in fluid communication. The inner space 540 is a hollow space delimited externally by the shell 5 and internally by the delimiting means 34. This inner space 540 is not a hose. The air inside the shell 5 is not conveyed by a hose (which would entail a pre-established air feed line), but it can move within the inner space 540 with greater freedom. This enables the air to envelop the delimiting means 34 (and advantageously, the compartment 3), thereby improving the cooling action. Moreover, by increasing the turbulence of the air inside the shell 5, the heat exchange may thereby also prove to be affected in a positive manner.

The inlet opening 21 is found below the outlet opening 22. More specifically, the inlet opening 21 is found below an axis 95 of rotation of the drum 4. As illustrated in the attached figures, the inlet opening 21 may be located in a lower base 94 of the household appliance 1 . Conveniently, the inlet opening 21 is located less than 30 centimetres from the resting plane surface of the household appliance 1 . Advantageously, the axis 95 of rotation of the drum 4 is substantially horizontal. The outlet opening 22 is found above the axis 95 of rotation of the drum 4. Advantageously, the outlet opening 22 is spaced over 60 cm from the resting plane surface of the household appliance 1 .

Conveniently, the ventilating means 6 comprises a plurality of inlet openings 21 . One or more of these inlet openings 21 (preferably all of them) conveniently have an inlet section greater than 5 cm². These inlet openings 21 are advantageously arranged side by side. Preferably, at least one plurality of these inlet openings 21 is horizontally aligned. In the solution illustrated by way of example, the openings are organised in a plurality of sets located side by side in a horizontal arrangement. Each one of these sets comprises a plurality of openings located one above the other.

The description referring to one of said inlet openings 21 can also be repeated for one or more of the remaining inlet openings 21 . Conveniently, the ventilating means 6 advantageously comprises a plurality of outlet openings 22. Conveniently, the description referring to one outlet opening 22 can be repeated for a plurality of said outlet openings 22. Conveniently, one or more of these outlet openings 22 (preferably all of them) have an outlet section greater than 5 cm².

In a particular structural solution, the ventilating means 6 is a means for forced ventilation (see Figure 3 for example). It comprises a fan 61 located downstream of said inlet opening 21 . The fan 61 forces the air passing through the opening 21 towards the delimiting means 34 of the compartment 3. The fan 61 is located inside the shell 5, less than 15 centimetres from the inlet opening 21 (or, in any case, from at least one of said inlet openings). Conveniently, the fan is an axial fan. The ventilating means 6 advantageously comprises a plurality of fans 61 , each fan being located downstream of at least one corresponding inlet opening 21 .

A method for drying laundry by means of a household appliance 1 is also an object of the present invention. The household appliance 1 can conveniently comprise one or more of the previously-described characteristics. The household appliance 1 conveniently comprises an outer shell 5 that contains delimiting means 34 for delimiting a drying compartment 3 for drying laundry. The compartment 3, in turn, contains a rotating drum 4 for holding the laundry (this is substantially tantamount to the fact that the delimiting means 34 contains the drum 4). The method comprises a stage that determines a condensation of at least part of the moisture present in the compartment 3 and generated by the wet laundry located in the drum 4, on at least part of the delimiting means 34 delimiting the compartment 3. The stage that determines the condensation of the moisture, in turn, comprises the stages of:

-introducing a flow of air inside the shell 5, having it travel through at least one inlet opening 21 afforded in a front wall 51 of the outer shell 5;

-conveying the flow of air from the inlet opening 21 to at least one outlet opening 22 located in a rear or side wall 52, 53, 54 of the shell 5; the stage of conveying the air flow comprises the stage of the flow of air flowing against the delimiting means 34 so as to determine a cooling thereof; the stage of flowing against the delimiting means 34 provides that the air flow come into contact with the delimiting means 34 externally of the compartment 3, but internally of the shell 5;

-having said flow of air flow outside the shell 5, having it travel through at least said outlet opening 22.

The stage of conveying the air from the inlet opening 21 to the outlet opening 22 can provide for surrounding the compartment 3 with the flow of air. Thus, in a preferred solution, there is an identifiable closed path surrounding the compartment 3 along which the flow of air flows.

The stage of conveying the air flow could take place spontaneously, for example through natural ventilation, taking advantage of a natural vent between the inlet opening 21 and the outlet opening 22. In fact, the air in contact with the delimiting means 34 subtracts heat from the compartment 3 and as it becomes warmer, it moves upwards spontaneously (where the outlet opening 22 is advantageously located). This attracts additional air from the inlet opening 21 below.

Movement of the air flow from the inlet opening 21 to the outlet opening 22 could take place through forced ventilation. In this case, it could take place by means of at least one fan 61 located inside the shell 5.

The stage of conveying the air flow from the inlet opening 21 to the outlet opening 22 provides for having the air flow travel inside the shell 5, but outside the compartment 3. Advantageously, this takes place without channelling the air inside a hose.

The stage of conveying the air flow from the inlet opening 21 to the outlet opening 22 provides for upward motion of the air flow that flows against an external surface of the delimiting means 34 without penetrating the compartment 3. The air flow thus comes directly in contact with a portion of the surface of the delimiting means 34 (without the interposition of hoses for conveying the air). Condensation of the moisture takes place on a surface that delimits the compartment 3 and that is part of the delimiting means 34. The condensation process therefore takes place within the delimiting means 34.

The present invention makes it possible to achieve multiple advantages. First of all, it makes it possible to minimize the costs of realising the household appliance. In fact, condensing the moisture already in the compartment 3 makes it possible to avoid (or reduce the use of) an additional condenser downstream of the compartment 3. The absence of a condenser also makes it possible to avoid the use of a supply solenoid valve supplying cooling liquid thereinside. An additional significant advantage is related to the possibility of operation of the household drying appliance even in the absence of a connection to the water supply network.

Furthermore, the use of air as a cooling fluid to bring about condensation of the moisture also permits savings on running costs (given the zero cost of the fluid utilised), while also markedly facilitating the conveying thereof without requiring special or specific channelling. Moreover, the use of air makes it possible to place the delimiting means 34 in direct contact with the air, without the intervention of the external wall of a conduit for channelling the cooling fluid (which is necessary in the case when any other fluid is utilised). This makes it possible to improve the efficiency of the heat exchange because the dissipation related to the presence of the channelling conduit is eliminated and because the air flow can envelop the compartment 3 on more than one side, thereby increasing the heat exchange surface area.

The invention thus conceived is susceptible to numerous modifications and variants, all of which falling within the scope of the inventive concept characterising the invention. Moreover, all the details may be replaced with other, technically equivalent elements. All materials used, as well as the dimensions, may in practice be of any type, according to requirements.

Claims

1 . A method for drying laundry by means of a household appliance (1 ) comprising an outer shell (5) that contains delimiting means (34) for delimiting an inner laundry drying compartment (3), said compartment (3), in turn, containing a rotating drum (4) for holding the laundry; said method comprising a stage that determines a condensation of at least part of the moisture present in the drying compartment (3) on at least a portion of the delimiting means (34), said moisture being determined by the laundry to be dried that is placed in the drum (4);

said method being characterised in that the stage that determines the condensation of the moisture, in turn, comprises the stages of:

-introducing a flow of air inside the shell (5), having it travel through at least one inlet opening (21 ) afforded in a front wall (51 ) of the outer shell (5);

-conveying the flow of air from the inlet opening (21 ) to at least one outlet opening (22) located in a rear or side wall (52, 53, 54) of the shell (5); the stage of conveying the air flow comprises the stage of the flow of air flowing against said delimiting means (34) so as to determine a cooling thereof; the stage of flowing against the delimiting means (34) provides that the air flow come into contact with the delimiting means (34) externally of the compartment (3), but internally of the shell (5);

-having said flow of air flow outside the shell (5), having it travel through at least said outlet opening (22).

2. The method according to claim 1 , characterised in that the stage of conveying the air from the inlet opening (21 ) to the outlet opening (22) provides for surrounding the compartment (3) with the flow of air.

3. The method according to claim 1 or 2, characterised in that the stage of conveying the air flow takes place through natural ventilation, taking advantage of a natural vent between the inlet opening (21 ) and the outlet opening (22).

4. The method according to claim 1 or 2, characterised in that the movement of the air flow from the inlet opening (21 ) to the outlet opening (22) takes place through forced ventilation by means of at least one fan (61 ) located inside the shell (5).

5. The method according to any one of the preceding claims, characterised in that the stage of conveying the air flow from the inlet opening (21 ) to the outlet opening (22) provides for having the air flow travel inside the shell (5), but outside the compartment (3) without channelling it into a hose; the air flow flowing directly against the delimiting means (34) as a consequence.

6. A household drying appliance comprising:

-delimiting means (34) for delimiting a drying compartment (3);

-a rotating drum (4) for containing laundry placed inside the drying compartment (3);

-a shell (5) external to the drying compartment (3), said shell comprising a front wall (51 ) and a rear wall (52) that are opposite one another and two side walls (53, 54) that are opposite one another and connecting the front wall (51 ) and the rear wall (52);

characterised in that it comprises ventilating means (6) for ventilating at least a first surface of the delimiting means (34) so as to determine the condensation of at least part of the moisture present in the compartment (3) and generated by the laundry to be dried and located in the drum (4), said first surface being external to the compartment (3), but contained within the shell (5);

said ventilating means (6) comprising an inlet opening (21 ) for an air flow into the shell (5) and an outlet opening (22) for the air flow out of the shell

(5); said inlet opening (21 ) being afforded in the front wall (51 ) of the household appliance (1 ) and said outlet opening (22) being afforded in the rear wall (52) or in at least one of said side walls (53, 54) of the shell (5).

7.The household appliance according to claim 6, characterised in that said shell (5) and said delimiting means (34) delimit, in combination, a space

(540) interposed therebetween that puts said inlet opening (21 ) and said outlet opening (22) in fluid communication.

8. The household appliance according to claim 6 or 7, characterised in that said inlet opening (21 ) is found below an axis (95) of rotation of the drum (4); said outlet opening (22) being found above the axis (95) of rotation of the drum (4).

9. The household appliance according to claim 6, or 7 or 8, characterised in that said ventilating means (6) is a means for forced ventilation and comprises a fan (61 ) located downstream of said inlet opening (21 ), said fan forcing the incoming air towards said delimiting means (34) for delimiting the compartment (3).

10. The household appliance according to claim 9, characterised in that said fan (61 ) is located less than 15 centimetres from said inlet opening (21 ).