WO2015003931A1

WO2015003931A1 - A household appliance wherein a dessicant is used in the drying step

Info

Publication number: WO2015003931A1
Application number: PCT/EP2014/063726
Authority: WO
Inventors: Yusuf YUSUFOGLU; Ali UNLUTURK; Yusuf Koc
Original assignee: Arcelik Anonim Sirketi
Priority date: 2013-07-10
Filing date: 2014-06-27
Publication date: 2015-01-15

Abstract

The present invention relates to a household appliance (1) comprising a tub (2) wherein the washing and/or the drying process is performed, an inlet port (3) providing the entry of air into the tub (2), an outlet port (4) enabling the air in the tub (2) to be discharged outside, a channel (5) extending between the inlet port (3) and the outlet port (4) so as to remain outside the tub (2), a receptacle (8) situated on the channel (5), a heater (7) disposed inside or in the vicinity of the receptacle (8), and a desiccant (9) that is situated inside the receptacle (8) and that is a super absorbent polymer.

Description

A HOUSEHOLD APPLIANCE WHEREIN A DESSICANT IS USED IN THE DRYING STEP

The present invention relates to a household appliance the energy consumption of which is decreased.

In household appliances like the dishwasher and dryer, the use of zeolite as the desiccant material, especially as the reversible desiccant material, is known for the aim of increasing the drying effectiveness and providing energy saving.

In these state of the art embodiments, the dishwasher comprises a receptacle that houses the desiccant and that is connected to the washing tub with an inlet and an outlet. In these embodiments, the wash water is heated by operating the heater disposed in the vicinity of the receptacle in the main washing step. At this moment, the fan is operated and the air received from inside the washing tub is passed over the receptacle. In the main washing step, the desiccant releases the retained moisture and thus completes its regeneration. In the drying step, the humid air sucked from the washing tub by means of the fan, is confined by the desiccant that has completed its regeneration in the main washing step while passing through the receptacle and that has become usable again. The dehumidified processing air is directed to the washing tub again, thus creating an air circulation. In desiccants with higher moisture retaining capacity than the zeolite, receptacles with larger volumes than the volume of the desiccant are used so as to compensate the increase in the volume after the moisture retaining process. The drying performance of the household appliance is adversely affected if the desiccant does not homogeneously spread in the empty space in the receptacle and/or the humid air leaves the receptacle without contacting the desiccant.

In the state of the art German Patent Application No. DE10353774, a dishwasher is explained wherein the air is passed over the desiccant in the drying step.

The aim of the present invention is the realization of a household appliance the energy consumption of which is decreased.

The household appliance realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a tub wherein items are placed for the purpose of drying and/or washing, an inlet port providing the entry of the processing air into the tub, an outlet port providing the exit of the processing air from the tub, a channel providing the formation of a closed air cycle between the inlet port and the outlet port, a receptacle disposed on the channel, a heater placed close to the receptacle, and a desiccant that is situated inside the receptacle and that is a super absorbent polymer. The household appliance of the present invention comprises a fan that is situated on the channel in the same vertical axis as the receptacle and that provides air flow from the receptacle towards the inlet port. It is possible to retain the moisture contained in the processing air by using a smaller amount of super absorbent polymer, the moisture retaining capacity of which is high relative to their unit weights. For this reason, super absorbent polymers occupy less space in the receptacle compared to other desiccants known in the technique, for example the zeolite. As a result of the super absorbent polymer being subjected to an air flow in reverse direction compared to the gravity, the super absorbent polymer can flutter around in the empty volume inside the receptacle by spreading homogeneously. Thus, effectiveness of the moisture retaining process is increased. Moreover, the effectiveness of the drying process is improved by preventing the humid air from passing from the receptacle towards the outlet port thanks to the air resistance in the receptacle in reverse direction compared to the gravity.

The household appliance comprises at least one separator that is situated in the receptacle and that separates the receptacle into at least two divisions. By means of the separator, the receptacle is separated into divisions wherein air currents flow in directions different from each other, thus, the humid air passes over the receptacle in a gradual manner and with reduced flow speed. The interaction time between the humid air with reduced flow speed and the desiccant is increased, thus improving the drying performance of the household appliance.

In an embodiment of the present invention, the desiccant is in powder form. The movement and the moisture retaining capacity of the desiccant increase as the surface area thereof becomes smaller. Thus, the desiccant retains moisture more easily.

In an embodiment of the present invention, the household appliance comprises an air-permeable, close porous sac that is situated in the receptacle and wherein the desiccant is filled. By means of the sac, the desiccant in powder or granule form can be easily placed into the receptacle and kept together in the receptacle.

In an embodiment of the present invention, the household appliance comprises a filter that is arranged on the inlet port and that prevents the desiccant from entering the tub. By means of the filter, the desiccant is prevented from being swept with the air current and from filling into the tub.

In an embodiment of the present invention, each particle of the desiccant is at least 1mm. Thus, the desiccant can be easily kept on the filter without clogging the filter.

In an embodiment of the present invention, the regeneration temperature of the desiccant is between 50°C and 100°C. The regeneration duration and the thermal energy required for regeneration decrease thanks to the property of the desiccant being able to be regenerated at low temperatures. The need for using high temperature resistant components is eliminated and thus material cost is reduced.

In an embodiment of the present invention, the glass transition temperature of the desiccant is between 20°C and 40°C. The moisture retaining capacity of the desiccant with high flexibility and low glass transition temperature is high.

In an embodiment of the present invention, the chamber has a flexible configuration. Thus, the chamber can expand during desiccation to compensate the increased desiccant volume.

In an embodiment of the present invention, the receptacle is produced from a material with high thermal conductivity. Consequently, heat loss during heat transfer from the heater situated in the vicinity of the receptacle to the desiccant is decreased.

In an embodiment of the present invention, the heater is disposed at a place in the vicinity of the receptacle, in a direction perpendicular to the air flow. Thus, almost all desiccant particles are facilitated to be regenerated since a homogeneous heat distribution is provided inside the receptacle. The total desiccation capacity of the desiccant increases in the next drying step and hence a more effective drying is provided.

The household appliance realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

Figure 1 – is the schematic view of the household appliance of the present invention.

The elements illustrated in the figure are numbered as follows:

Household appliance
Tub
Inlet port
Outlet port
Channel
Fan
Heater
Receptacle
Desiccant
Separator
Filter

The household appliance (1) comprises a tub (2) wherein the washing and/or the drying process is performed, an inlet port (3) providing the entry of air into the tub (2), an outlet port (4) enabling the air in the tub (2) to be discharged outside, a channel (5) extending between the inlet port (3) and the outlet port (4) so as to remain outside the tub (2), a receptacle (8) situated on the channel (5), a heater (7) disposed inside or in the vicinity of the receptacle (8), and a desiccant (9) that is situated inside the receptacle (8) and that is a super absorbent polymer. The humid air received from the tub (2) by means of the inlet port (3) is carried inside the channel (5) and directed to the receptacle (8) containing the desiccant (9) by means of a fan (6). Heat is emanated while moisture, carried by air, is bonded with the desiccant (9) due to the thermophysical property of the desiccant (9). The air, that is dehumidified and the temperature of which increases due to the heat emanated during dehumidification, is again directed into the tub (2). By means of this process, an effective drying process is realized by evaporating the water on the dishes. The desiccant (9) reaching the saturation point while retaining moisture is regenerated in the next washing step by means of the heater (7) disposed in the vicinity thereof and becomes usable again. The household appliance (1) of the present invention comprises a fan (6) that is situated below the receptacle (8), on the channel (5) and that provides air flow from the receptacle (8) towards the tub (2). The fan (6) situated below the receptacle (8) provides an air flow in reverse direction compared to the gravity and enables the desiccant (9) to flutter around in the receptacle (8). Thanks to the air resistance in the receptacle (8) in reverse direction compared to the gravity, the humid air is prevented from leaking from receptacle (8) and returning to the outlet port (4) while the area the humid air contacts the super absorbent polymer is increased.

The household appliance (1) comprises at least one separator (10) that is situated in the receptacle (8) and that separates the receptacle (8) into at least two divisions. By means of the separator (10), the receptacle (8) is separated into divisions that directs the air in a controlled manner, thus, the humid air passes over the receptacle (8) in a gradual manner and with reduced flow speed. The separators (10) are positioned in the receptacle (8) so as to turn the air in the opposite direction. Thus, the humid air with reduced speed is enabled to be passed over the desiccant (9) in a controlled manner and the interaction time thereof with the desiccant (9) is prolonged.

In an embodiment of the present invention, the desiccant (9) is in powder form. The desiccant (9) moves in the receptacle (8) more easily as the surface area thereof becomes smaller. The interaction area of the desiccant (9) with the humid air increases by the desiccant (9) in powder form moving by rotating with the effect of the air current.

In an embodiment of the present invention, the household appliance (1) comprises a porous sac with high air permeability that is situated in the receptacle (8) and wherein the desiccant (9) is filled. By means of the sac, the desiccant (9) in powder or granule form can be kept together in the receptacle (8).

In an embodiment of the present invention, the household appliance (1) comprises a filter (11) that is arranged on the inlet port (3) and that prevents the desiccant (9) from entering the tub (2). By means of the filter (11), the desiccant (9) is prevented from filling into the tub (2) due to the air current from the receptacle (8) towards the tub (2).

In an embodiment of the present invention, the household appliance (1) comprises the desiccant (9), of which each particle is at least 1mm. Thus, the desiccant (9) can be easily kept on the filter (11) without clogging the filter (11).

In an embodiment of the present invention, the regeneration temperature of the desiccant (9), which is a super absorbent polymer, is between 50°C and 100°C. The requirement for a powerful heater (7) is eliminated since the desiccant (9) is regenerated at low temperatures. The need for using high temperature resistant materials is eliminated and material cost is decreased since the temperature the components near the heater (7) are subjected to during the regeneration process decreases.

In an embodiment of the present invention, the desiccant (9) is a super absorbent polymer with a moisture retaining capacity that is approximately fifty percent of its mass. Thus, the use of a low weight desiccant (9) is sufficient and the material occupies less volume inside the receptacle (8). When the air flows into the receptacle (8), the desiccant (9) moves freely in the receptacle (8) and the interaction of the humid air with the desiccant (9) is improved.

In an embodiment of the present invention, the glass transition temperature of the desiccant (9) is between 20°C and 40°C. The desiccant (9) with low glass transition temperature has high flexibility and thus the porous structure can retain more moisture by expanding.

In an embodiment of the present invention, the receptacle (8) is formed from an elastic material. Thus, the receptacle (8) provides a flexible volume for the desiccant (9) that increases in volume while retaining moisture.

In an embodiment of the present invention, the receptacle (8) is formed from a material with high thermal conductivity. Thus, the heat transfer between the heater (7) situated in the vicinity of the receptacle (8) and the desiccant (9) inside the receptacle (8) is realized with less energy loss and the regeneration efficiency of the desiccant (9) increases.

In an embodiment of the present invention, the heater (7) is disposed near the receptacle (8) and in a direction perpendicular to the air flow. The heater (7) starts operating simultaneously with the fan (6) during the regeneration process. Heat transfer occurs by means of convection between the receptacle (8) and the heater (7) which is disposed perpendicular to the fan (6) and near the receptacle (8). Thus, the heat is enabled to be distributed homogeneously inside the receptacle (8), the regeneration efficiency of the desiccant (9) and hence moisture retaining capacity in the next drying step increase by means of the homogeneous heat distribution.

By means of the present invention, the air flows into the receptacle (8) in reverse direction compared to the gravity thanks to the placement of the fan (6) below the receptacle (8) so as to be almost in the same vertical axis with the receptacle (8). Thus, the desiccant (9) disperses and flutters around in the receptacle (8) and the drying effectiveness of the household appliance (1) is improved by increasing the interaction of the desiccant (9) with the humid air. Moreover, the effectiveness of the drying process is improved by preventing the humid air from passing from the receptacle (8) towards the outlet port (4) thanks to the air resistance in the receptacle (8) in reverse direction compared to the gravity.

Claims

A household appliance (1) comprising a tub (2) wherein the washing and/or the drying process is performed, an inlet port (3) providing the entry of air into the tub (2), an outlet port (4) enabling the air in the tub (2) to be discharged outside, a channel (5) extending between the inlet port (3) and the outlet port (4) so as to remain outside the tub (2), a receptacle (8) situated on the channel (5), a heater (7) disposed inside or in the vicinity of the receptacle (8), and a desiccant (9) that is situated inside the receptacle (8) and that is a super absorbent polymer, characterized by a fan (6) that is situated below the receptacle (8), on the channel (5) and that provides air flow from the receptacle (8) towards the tub (2).
A household appliance (1) as in Claim 1, characterized by at least one separator (10) that is situated in the receptacle (8) and that separates the receptacle (8) into at least two divisions.
A household appliance (1) as in Claim 1 or 2, characterized by the desiccant (9) in powder form.
A household appliance (1) as in any one of the above claims, characterized by a filter (11) that is arranged on the inlet port (3) and that prevents the desiccant (9) from entering the tub (2).
A household appliance (1) as in any one of the above claims, characterized by the desiccant (9), of which each particle is at least 1 mm.
A household appliance (1) as in any one of the above claims, characterized by the desiccant (9), the regeneration temperature of which is between 50°C and 100°C.
A household appliance (1) as in any one of the above claims, characterized by the desiccant (9) having moisture holding capacity that is approximately fifty percent of its mass.
A household appliance (1) as in any one of the above claims, characterized by the desiccant (9) the glass transition temperature of which is between 20°C and 40°C.
A household appliance (1) as in any one of the above claims, characterized by the receptacle (8) that is produced from elastic material.
A household appliance (1) as in any one of the above claims, characterized by the receptacle (8) that is formed from a material with high thermal conductivity.
A household appliance (1) as in any one of the above claims, characterized by the heater (7) that is disposed near the receptacle (8) and in a direction perpendicular to the air flow.