ITPN20100028A1 - WASH-DRYER WITH PARTICULARLY EFFICIENT DRYING - Google Patents

Description

â € œWASH-DRY WITH DRYING PARTICULARLY

EFFICIENT"

TECHNICAL FIELD OF INVENTION

[001] The present invention refers to a washing-drying machine for laundry capable of carrying out a drying cycle more efficiently than the corresponding machines of the known art. In particular, the washer-dryer machine is equipped with components designed so as not to alter, if not slightly increase, the efficiency of the washing cycle and surprisingly increase the efficiency of the drying cycle with considerable energy savings.

BASIC TECHNIQUE OF THE INVENTION

[002] The washing-drying machines currently on the market generally consist of a housing or piece of furniture suitable for enclosing all the components of the machine and equipped with an opening for accessing it. This opening can consist of a fully conventional front window or top door. Internally, a washer-dryer includes, as essential components, a tank suitable for containing water and for housing in a rotatable way a basket for washing / drying laundry, a motor to rotate the basket, a drain pump for the laundry. washing water and a drying system. The drying system in turn comprising a duct parallel to the tub and in communication with it and the drum, an air-water condenser positioned upstream of said duct, a fan for the circulation of air respectively in the duct, in the tub and in the drum and a heating resistance of the drying air downstream of the duct. Alternatively, the drying system can be constituted by a heat pump device, which is also completely conventional.

[003] Machines of this type are widely known in the household appliances sector, especially household appliances, and are operated in a suitable way so that they operate a complete washing cycle, that is, actual washing with or without prewash followed by draining the washing water and subsequent rinsing which ends with the spin cycle and the rinsing water drain phase. The washing cycle is then followed, if desired, in the same machine by the drying cycle.

[004] In particular, in order to carry out the washing cycle effectively, the drum of these machines consists of a hollow cylinder equipped, in the case of so-called front loading machines, with a bottom and an annular wall made with a sheet perforated stainless steel and an opening corresponding to the opening for access from the outside and opposite to said bottom. The bottom and the wall are perforated as they must allow the passage of water, both that loaded from the water mains at the beginning of the washing cycle and the washing or rinsing water already present in the tank. The holes must, therefore, be distributed substantially over the entire bottom and the wall in a uniform way and must have a diameter such as to allow on the one hand a good flow of water and on the other side prevent the laundry or parts of it. , such as buttons, zipper sliders, to come out of the basket itself. For this purpose, the holes conventionally have a diameter of around 5 mm.

[005] Furthermore, during the drying cycle, the aforesaid perforated structure of the drum allows a circulation of the drying air starting from the front opening both in an axial and radial direction with respect to the rotation axis of the drum itself.

[006] However, it has been observed that such machines suffer from a drawback linked above all to the efficiency of the drying cycle. In fact, it has been calculated that for example for a load of damp laundry of about 4 kg it takes about 3 hours for drying with an energy consumption of about 3-4 kWh per drying cycle and about 5-6 kWh for washing-drying cycle. The time required is obviously high and, consequently, also the energy consumption.

SUMMARY OF THE INVENTION

[007] The technical problem underlying the present invention is therefore that of devising a washer-dryer machine that allows to reduce the time required for drying and energy consumption and, at the same time, does not alter the efficiency of the washing cycle.

[008] This problem is solved by a washer-dryer machine equipped with technical devices such as to achieve a considerable reduction in the time and energy consumption of a drying cycle.

[009] A first object of the present invention is therefore a washer-dryer machine with a particularly efficient drying cycle.

[0010] A second object is a washing machine only or a dryer only.

[0011] A third object is a particular structure of the drum of said washer-dryer, washing machine or dryer.

BRIEF DESCRIPTION OF THE FIGURES

[0012] Further characteristics and advantages of the washing-drying machine of the invention will become more evident from the following description of an embodiment given purely by way of non-limiting example with reference to the following figures in which:

Figure 1 schematically represents the circulation of air in a washing-drying machine of the known art;

Figure 2 schematically represents the circulation of air in a washer-dryer machine according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0013] Figure 1 schematically shows the flow of air circulating in a circuit defined by a tub and a basket of a washer-dryer and by the drying device according to the known technique.

[0014] In particular, the machine 1 consists of a casing or piece of furniture 2 which encloses a tub 3 suitable for watertight containment and for housing in a rotatable manner a perforated basket 4 for handling linen.

[0015] The perforated basket 4 consists of a hollow cylinder equipped with a bottom 5 and an annular wall 6 made with a perforated stainless steel sheet and an opening 7 corresponding to the opening for access from the ™ external and opposite to said bottom. The bottom 5 and the wall 6 have holes 8 as they must allow the passage of water on one side, both that loaded from the water mains from the top at the start of the washing cycle and the washing water or already present in the tank, and on the other side the circulation of the drying air.

[0016] On the external surface of the bottom 5 there is a condenser 9 inside which a condensate fluid flows, designed to cool the internal walls of the condenser which, in turn, are passed through, separately from the condensate fluid, from the hot and humid air coming out of the drum 3. From the condenser 9 there is a duct 10 for the drying air, inside which there are means of circulation 11 and means of heating 12 of the air. The circulation means 11 are preferably represented by a fan which moves the air inside the duct 10 and the drum 4. The heating means 12 are preferably represented by an electric resistance.

[0017] In particular, as shown by the arrows inside the casing 2 of the machine 1, the air is pushed by the fan 11 through the resistance 12 so that it heats up. The hot air enters the tank 3 and the basket 4 mainly from the side of the opening 7, distributing itself along the X-X axis of the basket both radially with respect to said axis. Furthermore, part of the air will also go into the space between basket 4 and tub 3. After passing through the tub and basket, the hot air is charged with humidity and passes through the condenser 9 where it cools and releases the water contained in it by condensation. Finally, from condenser 9 the dry and cooled air returns to resistance 12.

[0018] It has been observed that as the laundry inside the drum dries, the flow of hot air directed in the axial direction is attenuated in favor of the radial one. In other words, the hot drying air passes mainly through the annular space or interspace between drum 4 and tub 3 as it would somehow seem to find an obstacle in entering the drum and distribute itself along a mainly longitudinal / axial flow.

[0019] It follows that a large part of the drying air would be dispersed outside the drum without crossing or, in other words, hitting the still damp laundry inside the drum. Above all, the laundry positioned more towards the bottom 5 of the drum 4 would be scarcely affected by the flow of the drying air.

[0020] In this way, obviously, the drying efficiency is compromised to the detriment, as previously mentioned, of energy consumption.

[0021] The idea behind the present invention is therefore to find a way to facilitate the passage of the drying air in the axial direction with respect to the radial one, even when the laundry tends to dry out and to give rise to the aforementioned problem .

[0022] It was thought to create a sort of undefined, momentary barrier or, in other words, a radial stop for the air that is activated at the beginning of the drying phase and ends with the end of the same phase.

[0023] To do this, a sort of cover, coat or cushion of the holes 8 present in the annular wall 6 was constructed.

[0024] With reference to Figure 2, a washing-drying machine 100 similar to the machine described above is schematically represented. This machine 100 also comprises a casing 200 or movable able to enclose all the components. Preferably, the machine 100 is of the front loading type with opening 210 which can be closed by a porthole 211. Internally, a tank 300 is suitable for watertight containment and for housing in a rotatable way a perforated basket 400 for handling linen.

[0025] Advantageously, the perforated basket 400 comprises an external cover 410 positioned so as to affect the annular wall 600 of the basket itself but not its bottom 500. It should be borne in mind that in figure 2 only a portion of the basket is covered from said cover 410, but obviously this extends over the entire external surface of said wall 600.

[0026] Preferably, the cover 410 is composed of a metal mesh comprising an intertwining of stainless steel metal wires intertwined in such a way as to constitute a number of meshes per square centimeter between 20 and 120, preferably between 50 and 100. In according to a particular embodiment, the number of stitches is about 60, in other words, the density of the stitch is 60 stitches per cm <2>.

[0027] Preferably, the threads that make up the mesh comprise two types of threads, one having a thread diameter of 0.12 mm and the other 0.07 mm and the density is 62.1 meshes per cm <2> ( 400 meshes per square inch).

[0028] It should be borne in mind that this mesh can have a number of threads per square inch, as well as the diameter of the threads themselves, greater or lesser than the preferred one just described. In fact, the mesh must be such as to function as a sort of cushion capable in some way of braking or creating turbulence on the external surface of the drum 400, as represented by the curved lines of Figure 2.

[0029] Probably, in fact, purely on a theoretical level, a mesh sufficient to create said turbulence would allow the formation of an annular zone of high pressure between the drum 400 and the tank 300 around the annular wall 600 of the drum itself. This high pressure zone would be countered by a low pressure zone at the opening 700 of the basket as well as inside the basket itself. It follows that, precisely due to the difference in pressure and apart from a first moment in which this difference in pressure must be created, the air tends to be sucked in and conveyed for the most part towards the inside of the basket and in the axial direction with consequent reduction of the head loss in the radial direction previously reported.

[0030] Preferably, moreover, a packing or annular gasket 420 can be arranged to close the space between the basket 400 and the tank 300, for example near the bottom 500 of the basket so as to further block the possibility of the flow passing radially in said space.

[0031] In accordance with a variant embodiment of the invention, the cover 410 can be arranged on the internal surface of the annular wall 600 of the basket instead of on its external surface.

[0032] Alternatively, two covers can be provided, one internal and one external with respect to the basket 400.

[0033] In a further variant, the basket 600 itself can be constituted by said cover. In other words, the perforated stainless steel sheet can be completely replaced by said cover which, therefore, would also extend to form the bottom of the basket. In this case, the mesh could be supported or reinforced with longitudinal crosspieces and annular reinforcement bands integral with each other so as to create a sort of trellis or rigid support structure to be able to be rotated by the engine safely both at low rpm. during washing and at high revolutions during the spin cycle.

[0034] In a further variant, the mesh 410 could involve only the holes 800, ie it can be obtained directly in the opening of the holes. In this case, the holes could also have quite large dimensions compared to conventional holes since their opening could be easily engaged by a sort of discs produced with the aforementioned mesh. In fact, regardless of how said holes 800 are covered, it is important that there is sufficient light to let the water pass and at the same time sufficient weaving of the weft to create the aforementioned sort of turbulence or air cushion.

[0035] In addition, it should be noted that the mesh 410 can also be produced with plastic threads such as nylon or other polymer resistant to high temperatures such as those used during a normal washing cycle or drying cycle. Also in this case, the nylon mesh can be fixed to the basket in various ways, internally or externally, possibly with the help of a frame. Alternatively, a microporous material can be used to construct the entire basket 400 or the mesh 600. Microporous materials such as those used for membranes or filters are known in various sectors. In particular, a sintered metal-based material can be used.

[0036] The openings of the mesh, or mesh gap, can also vary from 0.005 mm to 0.2 mm so as to have the aforementioned function of creating turbulence or a sort of cushion.

[0037] Similarly, the diameter of the wires, whether metal or plastic or of other suitable material, can vary from 0.01 mm to 3 mm.

[0038] The weft can also be ordered, as schematically represented in the enlargement of figure 2, or random and arranged so as to form a single or multilayer mesh and with variable thicknesses. For example, the knit can be made up of a non-woven fabric composed of continuous fibers or filaments of high mechanical strength and high temperature resistant, hydro-entangled polymeric material. Furthermore, the light of the mesh can be regular, for example circular, triangular, square, more generally regular polygonal, or irregular, random.

[0039] In accordance with the embodiment shown in Figure 2, the machine 100 further comprises a drying device of the heat pump type. As previously mentioned, this device is known per se and, in general, comprises an operating unit 110, a delivery duct 111 for the drying air and a recovery duct 112 for the humid hot air.

[0040] The operating unit 110, in turn, comprises a refrigeration circuit consisting of an evaporator 113, a compressor 114, a condenser 115 and a lamination valve 116. Furthermore, in correspondence with the coupling with the flow 111, air handling means 117 are positioned, such as a fan. As is known, a refrigerant fluid circulates inside the refrigeration circuit passing through the evaporator 113 where it cools the hot and humid air coming from the machine 100 and at the same time acquires the heat of said air through thermal exchange. The humidity contained in said air condenses on the external surface of the evaporator and is thus dehumidified. Subsequently, the refrigerant fluid passes through the compressor where it undergoes further heating and is pushed to the condenser 115. Here the cooled and dehumidified air is heated by said fluid and pushed by the fan 117 inside the delivery duct 111 in so as to reach the drum 400. At the same time, the refrigerant fluid which has transferred the heat to the heating air passes through the lamination valve 116 at the outlet of which it is further cooled and then reaches the evaporator 113 again and starts again the cycle.

[0041] Obviously, the example just described of a drying device of the heat pump type can be replaced by a more conventional simple condensing device such as the one reported in the introductory part of the present description and schematically represented in figure 1.

[0042] Furthermore, the example of embodiment of the invention preferably relates to a combined washer-dryer machine. Nevertheless, the inventive concept of the cover explained above can also be applied to a dryer-only machine or, at most, to a washing-only machine in the event that, as described, it is desired to make a basket equipped with an annular wall with diameter holes greater than the conventional one and engaged by a link like the one shown in accordance with the invention. In this case, the advantage would be to have in a single basket that can also be used for a single washing machine without affecting the washing cycle as the holes always allow the passage of water in the basket but prevent the spillage of laundry or parts of it. thanks to the weaving of the shirt. In addition, the use of a mesh positioned inside the drum, or in any case at the level of its holes, creates an uneven surface against which the laundry would be rubbed in some way, thus increasing the effectiveness of the washing. .

[0043] Further variants of the washing-drying machine of the present invention can be made by the expert, however without departing from the scope of protection defined by the claims attached hereafter.

Claims (10)

â € œWASH-DRY WITH PARTICULARLY EFFICIENT DRYING " CLAIMS 1. Washing-drying machine (100), washing machine or dryer comprising a casing (200) adapted to house a tub (300) in turn adapted to contain watertight and adapted to rotatably house a perforated basket (400) having a bottom (500) and an annular wall (600) for moving laundry, characterized in that at least a portion of said drum (400) comprises a mesh (410) consisting of an intertwining of metal and / or plastic threads having density between 20 stitches per cm <2> and 120 stitches per cm <2>. Machine (100) according to claim 1, wherein the annular wall (600) of said basket (400) is externally and / or internally coated by said mesh. Machine (100) according to claim 1, wherein said mesh (410) covers only the holes (800) of said basket (400) from its internal and / or external side. 4. Machine (100) according to claim 1, wherein said link (410) is integrated in the opening of the holes (800) of said basket (400). 5. Machine (100) according to claim 1, in which both the bottom (500) and the wall (600) of said basket (400) consist mainly of said mesh (410) possibly supported by longitudinal crosspieces and annular support bands . Machine (100) according to any one of claims 1 to 5, in which the mesh (410) is made up of metal and / or plastic wires preferably selected from stainless steel wires and nylon or other high-strength polymer wires mechanics and resistance to high temperatures, said threads being arranged so as to form said mesh according to a regular or irregular weft. Machine (100) according to claim 6, wherein said mesh (410) is composed of stainless steel wires having a diameter of 0.12 mm and 0.07 mm. Machine (100) according to claim 7, wherein the density of said stitch is about 60 stitches per cm <2>. Washing-drying or drying machine (100) according to any one of claims 1 to 8, further comprising a drying device selected from a simple condensing device and a heat pump device (110). Basket (400) for treating laundry of a washer-dryer, washer or dryer machine (100) comprising a mesh (410) according to any one of claims 1 to 8.