EP2449164B1

EP2449164B1 - A laundry dryer the drying effectiveness of which is increased

Info

Publication number: EP2449164B1
Application number: EP10725184A
Authority: EP
Inventors: Onur Hartoka; Yavuz Sahin; Erdem An; Mehmet Kaya
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2009-06-29
Filing date: 2010-06-16
Publication date: 2013-03-20
Anticipated expiration: 2030-06-16
Also published as: EP2449164A1; WO2011000705A1

Description

The present invention relates to a laundry dryer, the drying effectiveness of which is increased.
In dryers having a closed cycle, the cycle air, after performing the moisture absorption process from the laundry, is cooled by being passed through a cooling system and the water vapor contained therein is provided to be condensed known, for instance, from DE-A-10 2005 062 804 . After the condensation process, the cycle air is passed over a heater and delivered to the drum again, thereby also providing to evaporate the moisture remaining on the laundry. The laundries are dried at the end of this process repeated in a closed cycle. In air cooled systems, the cycle air is cooled with the ambient air by being passed through the cross-flow condenser and thus, the condensation process is provided to be performed. However, since the water retaining performance of the condenser is not 100 %, the cycle air that passes through the condenser contains some moisture. This, in turn, affects the laundry drying effectiveness quite adversely. Furthermore, another condition affecting the drying process is providing the distribution of the cycle air inside the drum as homogeneously as possible.
In the current situation, as a result of the high temperature cycle air contacting firstly with the laundry on the rear side of the drum, the laundry located at the rear side of the drum and the laundry located at the front side of the drum cannot be dried at the same rate and this adversely affects the drying speed and the consumption of energy.
In the state of the art U.S. Patent No US5279047 , a laundry dryer is explained wherein the condenser is integrated in the door.
In the state of the art, the use of Peltier elements that operate according to the thermoelectric effect principle in order to increase the drying effectiveness is known.
The aim of the present invention is the realization of a laundry dryer, the drying effectiveness of which is increased.
The laundry dryer realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a Peltier element located on the door, extending from the loading port into the drum when the door is closed, disposed between the inlet and outlet of the casing through which the cycle air received from the drum passes, such that the cold surface will face the inside of the casing and the hot surface inside of the drum. The casing serves as a channel, through which the cycle air flows while the door is closed and which provides the direction of the cycle air to the condenser.
Thus, while the hot and moist cycle air received from the drum is condensed on the cold surface, the front portion of the drum is heated by the hot surface and while providing homogeneous heat distribution inside the drum, the condensation effectiveness is also increased.
The laundry dryer comprises a sealing element that prevents the cycle air or the water condensed on the cold surface from leaking into the drum or to the outside surrounding while the air passing through the casing is directed to the condenser when the door is closed. The sealing element surrounds the outlet of the casing when the door is closed.
The laundry dryer, furthermore, comprises fins situated on the cold and hot surfaces, increasing the heat transfer surface area by extending towards the inside of the casing and inside of the drum, respectively.
By means of the present invention, the drying time and the energy consumption are decreased. Furthermore, the laundry is provided to be dried more homogeneously by improving the heat distribution in the drum.
A laundry dryer 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 laundry dryer.
Figure 2 - is the schematic view of a door.
The elements illustrated in the figures are numbered as follows:

1. Laundry dryer
2. Body
3. Front wall
4. Drum
5. Heater
6. Condenser
7. Fan
8. Door
9. Reservoir
10. Casing
11. Inlet
12. Outlet
13. Peltier element
14. Sealing element
15. Fin

The laundry dryer (1) of the present invention comprises a body (2) having a front wall (3), a drum (4) wherein the laundry desired to be dried is placed, a loading port that is located on the front wall (3) and that provides access into the drum (4), a door (8) covering the loading port, a condenser (6) that condenses and hence provides the dehumidification of the cycle air leaving the drum (4), a heater (5) that provides the heating of the dehumidified cycle air leaving the condenser (6), and at least one fan (7) that maintains the cycle air to be circulated in a closed cycle.
The laundry dryer (1), furthermore, comprises a casing (10) located on the door (8) and disposed at the rear of the door (8), extending from the loading port towards the inside of the drum (4) when the door (8) is closed, having an inlet (11) that provides the cycle air leaving the drum (4) to enter therein and an outlet (12) that provides it to pass to the condenser (6). Thus, before entering the condenser (6), the cycle air, laden with the moisture retained from the laundry in the drum (4), thereafter passes to the casing (10) from the inlet (11) and is directed from the casing (10) outlet (12) towards the condenser (6). The casing (10) serves as a channel wherein the cycle air passing through the drum (4) moves forward and which provides the cycle air to be delivered to the condenser (6) when the door (8) is closed.
The laundry dryer (1) comprises at least one Peltier element (13) mounted to the casing (10) between the inlet (11) and the outlet (12) such that the cold surface (C) will face the inside of the casing (10) and the hot surface (H) inside of the drum (4) (Figure 1 and Figure 2). The Peltier element (13) is formed by joining together the cold and hot surfaces (C and H) back to back. When the Peltier element (13) is driven by electricity, while the hot and moist air entering into the casing (10) from the drum (4) is condensed on the cold surface (C), the front portion of the drum (4), hence the laundry situated therein is heated by the hot surface (H) facing the inside of the drum (4) at the same time. Thus, by means of the cold surface (C), both the condensation effectiveness of the laundry dryer (1) is increased and the heat distribution inside the drum (4) is provided to be homogeneous.
In an embodiment of the present invention, the inlet (11) and the outlet (12) are on the same direction, and the inlet (11) is on the ceiling of the casing (10) and the outlet (12) is on the base of the casing (10).
The cycle air is received into the casing (10) through the inlet (11) situated above the casing (10). Some of the moisture contained in the cycle air entering into the casing (10) is condensed on the cold surface (C) while passing through the cold surface (C) of the Peltier element (13) before entering the condenser (6). The cycle air, with some of the moisture contained therein condensed on the cold surface (C), passes through the outlet (12) and is directed towards the condenser (6). Meanwhile, the Peltier element (13) hot surface (H) situated on the surface of the door (8) facing the inside of the drum (4) delivers the heat contained therein into the drum (4) and hence to the laundry. The cycle air passing through the condenser (6) virtually leaves the moisture, which cannot be condensed by the cold surface (C), in the condenser (6), and is heated by the heater (5) and thus, is received into the drum (4) to be transferred onto the laundry. Accordingly, almost dry and hot air is delivered onto the laundry in the drum (4).
The laundry dryer (1) comprises one or more sealing elements (14) that surround the outlet (12) of the casing (10) and thus, prevent the cycle air and the water condensed on the cold surface (C) from leaking into the drum (4) and to the outside.
The laundry dryer (1) comprises one or more fins (15) that are located on the cold surface (C) and extend towards the inside of the casing (10), and that are located on the hot surface (H) and extend towards the inside of the drum (4), and that increases the heat transfer surface area.
The laundry dryer (1) comprises a reservoir (9) on the base of the body (2), at the place corresponding to the casing (10) outlet (12) when the door (8) is closed, wherein the water condensed on the cold surface (C) is collected. The water collected on the cold surface (C) passes from the casing (10) outlet (12) and is accumulated in this reservoir (9).
By means of the present invention, the condensation speed increases since the cold surface (C) serves an additional condensing function to the condenser (6) and the drying speed increases since the hot surface (H) serves an additional heating function to the heater (5). The laundry inside the drum (4) is provided to be dried more homogeneously since the front side of the drum (4) is heated by the hot surface (H).
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.

Claims

A laundry dryer (1) comprising a body (2) which has a front wall (3), a drum (4) wherein the laundry desired to be dried is placed, a loading port which is located on the front wall (3) and provides access into the drum (4), a door (8) which covers the loading port, a condenser (6) which provides the cycle air leaving the drum (4) to be dehumidified by being condensed, a heater (5) which provides the heating of the dehumidified cycle air leaving the condenser (6), and at least one fan (7) which provides the cycle air to be circulated in a closed cycle, and characterized by
- a casing (10) which is located on the door (8) and disposed at the rear of the door (8), and which extends from the loading port towards the inside of the drum (4) when the door (8) is closed, and which has an inlet (11) that provides the cycle air leaving the drum (4) to enter therein and an outlet (12) that provides it to pass to the condenser (6) and

- at least one Peltier element (13) which is mounted to the casing (10) between the inlet (11) and the outlet (12) such that the cold surface (C) will face the inside of the casing (10) and the hot surface (H) the inside of the drum (4).
A laundry dryer (1) as in Claim 1, characterized by the casing (10) which has an inlet (11) located on the ceiling and an outlet (12) located on the base, both being disposed in the same direction.
A laundry dryer (1) as in Claim 1 or 2, characterized by one or more sealing elements (14) which prevent the cycle air and the water condensed on the cold surface (C) from leaking into the drum (4) and to the outside by surrounding the outlet (12) of the casing (10).
A laundry dryer (1) as in Claim 1 or 2, characterized by one or more fins (15) which are located on the cold surface (C), extend towards the inside of the casing (10) and which are situated on the hot surface (H), extend towards the inside of the drum (4), and which increase the heat transfer surface area.
A laundry dryer (1) as in any one of the above Claims, characterized by a reservoir (9) which is on the base of the body (2), at the place corresponding to the level of the door (8) when the door (8) is closed, and wherein the water condensed on the cold surface (C) is collected.