WO2012089514A1

WO2012089514A1 - A dishwasher comprising a thermoelectric module

Info

Publication number: WO2012089514A1
Application number: PCT/EP2011/072843
Authority: WO
Inventors: Serdar Kocaturk; Feyzi Alper SOYSAL; Yalcin Guldali
Original assignee: Arcelik Anonim Sirketi
Priority date: 2010-12-27
Filing date: 2011-12-15
Publication date: 2012-07-05
Also published as: EP2658429A1; EP2658429B1

Abstract

The present invention relates to a dishwasher (1) comprising a tub (2) wherein the washing process is performed, an air channel (6) located outside the tub (2), both ends of which are connected to the tub (2), an inlet port (3) which provides the air in the tub (2) to enter the air channel (6), an outlet port (4) which provides the air in the air channel (6) to return back to the tub (2), a fan (5) which sucks and delivers the air in the tub (2) to the air channel (6) and a thermoelectric module (7) disposed in the air channel (6), having a cold side (8) that provides the dehumidifying air to be condensed and a hot side (9) that provides it to be heated, and the dehumidification performance of which is increased.

Description

A DISHWASHER COMPRISING A THERMOELECTRIC MODULE

The present invention relates to a dishwasher comprising a thermoelectric module.

In dishwasher programs, the dehumidification step is started after the washing and rinsing steps. In the dehumidification step, it is aimed to remove the water remaining on the dishes and also to prevent the moisture in the tub from leaving stains on the dishes getting cold after the rinsing step by condensing. The last rinsing step is performed with hot water in order to remove the water remaining on the dishes in an easier way in the dehumidification step. In the dehumidification step after the hot rinsing step, humid air in the tub is passed through a channel produced from plastic material and situated next to the tub. When the air circulated inside the said channel by means of a fan contacts the surfaces of the channel which are cold with respect to the inside of the tub, some of the moisture in the air can be condensed but the tub cannot be completely dehumidified and stain formation is observed on the washed items due to the moisture that remains at the end of the dehumidification phase. Moreover, when the user opens the cover of the dishwasher just after the program is completed, air mass with high temperature remaining in the tub at once exits to the outer environment and can cause the user to be exposed to hot vapor.

Moreover, in the dehumidification process in dishwashers, thermoelectric modules, which provide the hotness and coldness effect to be emitted to the environment according to the direction of the current applied thereon, are utilized but devices that accelerate the dehumidification process such as condenser, heater are also required besides thermoelectric modules.

In the state of the art International Patent Application No WO2005018408, a dishwasher is described which comprises a thermoelectric module disposed on the air channel. In this embodiment, the humid air received from the tub first condenses by passing from the cold side of the thermoelectric module and then heats up by passing from the hot side of the thermoelectric module and is returned back into the tub.

In the state of the art International Patent Application No. WO2006029953, a dishwasher is described which comprises a thermoelectric module positioned between the tub and the air channel. In this embodiment, the hot side of the thermoelectric module increases the temperature of the air that passes through the air channel by contacting the air channel and the cold side is used for cooling the tub wall.

The aim of the present invention is the realization of a dishwasher wherein the moisture that remains in the tub at the end of the washing process is effectively removed.

In the dishwasher realized in order to attain the aim of the present invention, an air channel located outside the tub, both ends of which are connected to the tub and a thermoelectric module disposed in the air channel are situated.

The thermoelectric module includes a cold side which forms a coldness effect by absorbing the ambient heat and a hot side which radiates heat to the environment. The hot and cold sides of the thermoelectric module are positioned so as to be base to base.

The air channel comprises a condensing channel whereon the cold side of the thermoelectric module is disposed and a heating channel whereon the hot side of the thermoelectric module is disposed, which divide the air entering therein into two such that the air flows parallel. The heating and the condensing channels are separated from each other by means of a surface which separates the surface of the air channel cross-section into two. The thermoelectric module is placed on the said surface such that the cold side thereof extends into the condensing channel and the hot side extends into the heating channel.

In an embodiment of the present invention, heat exchangers, which provide the heat in the respective region to be distributed into the channel in which the heat exchanger is located, are disposed on the cold side and the hot side of the thermoelectric module. The heat exchanger disposed on the cold side is called the cold side heat exchanger and the heat exchanger disposed on the hot side is called the hot side heat exchanger. Both of the heat exchangers are preferably in finned configuration. By changing the lengths of the fins of the heat exchangers, the speed and the amount of the air received into the channel wherein the heat exchangers are located can be changed.

In another embodiment of the present invention, the heating channel has a cross-sectional area greater than that of the condensing channel. Since the air received into the air channel through the inlet port has the characteristic of being almost homogeneously dispersed along the air channel cross-section, the rate of the cross-sectional areas of the heating and condensing channels determines the rate of the amount of the air entering the said channels.

In the dishwasher of the present invention, the air the temperature of which increases inside the heating channel increases the tub ambient temperature and provides the water on the dishes to be removed. Thus, energy saving is provided by decreasing the temperature value to be reached by the tub at the end of the hot rinsing step and hence the operation duration of the heater in the said step. Moreover, the amount of the moisture in the air in the tub is decreased in the condensing channel. Thus, the humid air is prevented from leaving stains on the dishes by condensing after the rinsing step.

The dishwasher 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 a dishwasher.

The elements illustrated in the figures are numbered as follows:

Dishwasher
Tub
Inlet port
Outlet port
Fan
Air channel
Thermoelectric module
Cold side
Hot side
Condensing channel
Heating channel
Cold side heat exchanger
Hot side heat exchanger

The dishwasher (1) comprises a tub (2) wherein the washing process is performed, an air channel (6) located outside the tub (2), both ends of which are connected to the tub (2), an inlet port (3) which provides the air in the tub (2) to enter the air channel (6), an outlet port (4) which provides the air in the air channel (6) to return back to the tub (2), a fan (5) which sucks and delivers the air in the tub (2) to the air channel (6) and a thermoelectric module (7) disposed in the air channel (6).

The thermoelectric module (7) comprises a cold side (8) that provides the dehumidifying air to be condensed and a hot side (9) that provides it to be heated.

In the dishwasher (1) of the present invention, the air channel (6) comprises a condensing channel (10) contacting the cold side (8) of the thermoelectric module (7) and a heating channel (11) contacting the hot side (9), which are positioned so as to be back to back and which provide the air entering therein to flow parallelly by being divided into two and to return back to the tub (2) by joining (Figure 1).

As a result of the evaporation of the water in the tub (2) due to the high temperature during the operation of the dishwasher (1), high relative humidity values are reached in the tub (2) at the beginning of the dehumidification step. In the dishwasher (1) of the present invention, by the starting of the dehumidification step, the thermoelectric module (7) is activated and while the temperature of the cold side (8) decreases, the temperature of the hot side (9) increases. By means of the fan (5) which is activated almost simultaneously with the thermoelectric module (7), the air in the tub (2) is received to the air channel (6). After moving through the air channel (6) for a while, the humid air is divided into two. While some of the air enters the condensing channel (10) cooled by means of the cold side (8) of the thermoelectric module (7), the rest enters the heating channel (11) heated by means of the hot side (9) of the thermoelectric module (7). The air with increased temperature that exits the heating channel (11) and the air with decreased moisture rate that exits the condensing channel (10) join at a point of the air channel (6) close to the outlet port (4) and return back to the tub (2) from the outlet port (4). Thus, by increasing the tub (2) interior temperature, the water remaining on the dishes is provided to be removed and the amount of the moisture in the tub (2) is provided to be reduced.

In an embodiment of the present invention, the dishwasher (1) comprises a cold side (8) heat exchanger (12) disposed on the cold side (8) of the thermoelectric module (7), extending towards into the condensing channel (10) and which contacts and thus accelerates the condensing of the air passing through the condensing channel (10) and a hot side (9) heat exchanger (13) disposed on the hot side (9) of the thermoelectric module (7), extending towards into the heating channel (11) and which contacts the air passing through the heating channel (11) and thus accelerates the heat transfer. By means of the said heat exchangers (12, 13), the hotness effects in the condensing channel (10) and the heating channel (11) are emitted inside the channel.

In another embodiment of the present invention, the cross-sectional area of the heating channel (11) is greater than the cross-sectional area of the condensing channel (10). Thus, the amount of the air received into the heating channel (11) is provided to be greater than the amount of the air received into the condensing channel (10). Thus, the thermoelectric module (7) operates more efficiently and the dehumidification effectiveness of the dishwasher (1) is provided to be increased.

By means of the present invention, in the dehumidification step, the temperature of the air in the tub (2) is increased and the moisture thereof is decreased. Consequently, the tub (2) interior temperature to be reached at the end of the rinsing step in order to realize the desired dehumidification performance is decreased. Accordingly, the heater used for heating the water in the hot rinsing step is operated for a shorter period of time and energy saving is provided. Moreover, the humid air in the tub (2) is prevented from leaving stains on the dishes after the rinsing step by condensing.

It is to be understood that the present invention is not limited to the embodiments disclosed above and a person skilled in the art can easily introduce different embodiments. These should be considered within the scope of the protection postulated by the claims of the present invention.

Claims

A dishwasher (1) comprising a tub (2) wherein the washing process is performed, an air channel (6) located outside the tub (2), both ends of which are connected to the tub (2), an inlet port (3) which provides the air in the tub (2) to enter the air channel (6), an outlet port (4) which provides the air in the air channel (6) to return back to the tub (2), a fan (5) which sucks and delivers the air in the tub (2) to the air channel (6) and a thermoelectric module (7) disposed in the air channel (6), having a cold side (8) that provides the dehumidifying air to be condensed and a hot side (9) that provides it to be heated, characterized by the air channel (6) providing the air entering therein to flow parallelly by being divided into two and to return back to the tub (2) by joining and having

- a condensing channel (10) contacting the cold side (8) of the thermoelectric module (7) and

- a heating channel (11) contacting the hot side (9) thereof,

which are positioned so as to be back to back.
A dishwasher (1) as in Claim 1, characterized by a cold side (8) heat exchanger (12) disposed on the cold side (8) of the thermoelectric module (7), extending towards into the condensing channel (10) and which contacts and thus accelerates the condensing of the air passing through the condensing channel (10).
A dishwasher (1) as in any one of the above claims, characterized by a hot side (9) heat exchanger (13) disposed on the hot side (9) of the thermoelectric module (7), extending towards into the heating channel (11) and which contacts the air passing through the heating channel (11) and thus accelerates the heat transfer.
A dishwasher (1) as in any one of the above claims, characterized by the heating channel (11) the cross-sectional area of which is greater than the cross-sectional area of the condensing channel (10).