EP1960586B1 - Apparatus and method for loading items to be washed with an air flow - Google Patents

Abstract

An apparatus for loading items to be washed with an air flow, comprising a substantially closed first channel system for guiding an air flow which loads the items to be washed. A treatment chamber for receiving the items to be washed, a blower for driving the air flow, a heater for heating the air flow before the items to be washed are loaded, and a cooler for cooling the air flow after the items to be washed have been loaded are arranged in the first channel system. Here, the first channel system has outside the treatment chamber and the blower, two branches and which are connected to one another in parallel and can be flowed through in parallel by corresponding parts of the air flow. Here, the heater is arranged in a first branch and the cooler is arranged in a second branch of said branches. The invention likewise relates to a corresponding method.

Description

The invention relates to a device for applying laundry with an air stream, comprising a substantially closed first channel system for forcibly guiding an air stream acting on the laundry, in which first channel system a treatment chamber for receiving the laundry, a fan for driving the air flow, a heater for Heating the air flow before applying the laundry and a cooler for cooling the air flow after the application of the laundry are arranged. The invention also relates to a method for applying laundry with an air stream, which is forcibly guided in a first channel system just described.

Such a device and such a method will be apparent from the EP 0 467 188 B1 , the disclosure of which is fully attributable to this disclosure. In the device there for drying laundry, the heater and the cooler are components of a heat pump device, and in this heat pump device, the cooler forms an evaporator and the heater forms a condenser for a circulating in an associated circuit working fluid. The first duct system, in which the air flow is guided, is substantially closed - this means that the air flow circulates in the normal operation substantially without leaks, but does not assume a much higher pressure than air in the vicinity of the device. The air flow is thereby driven essentially by the blower and thus forcibly guided through the first duct system; Convection and the like buoyancy effects play at most a minor role to drive the air flow. If desired, the duct system can be brought into contact with the environment by opening a door, in particular to discharge part of the airflow heated during operation from the apparatus and to replace it with relatively cool ambient air. The treatment room for receiving the laundry is designed as a rotatable drum.

From the DE 1 410 206 A is a washing machine, in which laundry not only washed, but also can be dried. For the required additional facilities, the font shows several alternatives; In particular, an electric heating device for heating an air stream used for drying laundry and a simple heat exchanger for cooling the heated air stream after the loading of the laundry may be provided, but the heater and the cooler may also belong to a heat pump device. The heat pump device may be configured as in the EP 0 467 188 B1 It may also be a heat pump device which uses Peltier elements to utilize the thermoelectric effect.

From the DE 19 738 735 C2 is a device for drying laundry of the type described input forth, in which a heat pump device is used, which operates on an absorber principle.

One from one in the "Patent Abstracts of Japan" data collection JP 08 057 194 A proper English Kurzauszug resulting device for drying laundry, which in turn corresponds to the type described input, contains in its first channel system in addition to a heater and a radiator, both of which belong to a thermoelectrically operable heat pump, a cooler upstream of the additional heat exchanger for cooling the of the Laundry goods discharged air flow and a heater downstream additional heating device for further heating of the air flow before applying the laundry. Also from the DE 3 509 549 A1 shows a device for drying laundry, which in addition to a heat pump device with cooler and heater has a further heating device and additional heat transport devices such as gravity heat pipes.

All the devices and methods of the prior art described have in common that their components required for acting on the laundry with the air flow are arranged behind one another in the channel system provided for guiding the air flow. Such an arrangement has specific requirements for implementation in a suitable and suitable for use in a normal household device. These requirements may be due to only limited space available that components of the duct system must be relatively small and therefore run with relatively high flow resistance for the air flow; This may be the effect of in the device To significantly affect the ongoing drying process, since a flow of air with limited volume flow rate must be driven by a possibly causing considerable friction and throttling losses channel system. This problem is particularly pronounced when a heat pump device is to be used in the device, in particular a thermoelectric heat pump device. Particularly in the case of the thermoelectric heat pump device, in a device which is used in a household tumble dryer with conventional outer dimensions, the duct system must be folded several times.

From the DE 32 04 718 A1 is a drying apparatus for drying laundry by means _produces' a flow of air having a dry chamber for receiving the laundry, a heating element for heating the air flow, and a condensing element for separating moisture from the air stream. In this case, to drive the air flow in each case used up and down effects, which arise by heating or cooling of the air flow or a portion of the air flow. In particular, a buoyancy effect in the heating element is used in each described embodiment of the drying apparatus. The condensation element may include a combination of a fan and a valve to assist in its action; the heating element and the condensation element may be corresponding components of a heat pump system.

The JP 4-352999 A discloses a device or a method according to the respective preamble of claims 1 and 12, respectively.

Details on the basics, function and application of Peltier elements can be found in documents published on 25 November 2005 from the Internet addresses http://www.quick-ohm.de/waerme/download/Erlaeuterung-zu-Peltierelementen.pdf
and
http://www.quick-ohm.de/waerme/download/Einbau.pdf
were downloadable.

Accordingly, the invention to be described below, inter alia, based on the task of specifying a device and a method of the type described input, which avoid the disadvantages described above of a many components contained consecutively and possibly multi-folded channel system.

To solve this problem, a device for drying laundry, comprising a substantially closed first channel system for forcibly guiding an air stream acting on the laundry, in which first channel system a treatment chamber for receiving the laundry, a fan for driving the air flow, a heater for Heating the air flow before the loading of the laundry and a cooler for cooling the air flow after the loading of the laundry are arranged, in which device according to the invention, the first channel system outside the treatment chamber and the fan has two parallel branches, which are parallel from corresponding parts of the air flow can be flowed through, wherein the heater is arranged in a first branch and the radiator in a second branch of these branches, wherein the heater and the radiator belonging to a heat pump means.

To solve this problem also stated is a method for applying laundry with an air flow, which is forcibly guided in a substantially closed first channel system, in which first channel system, a treatment chamber for receiving the laundry, a blower for driving the air flow, a heater for Heating the air flow before applying the laundry and a cooler for cooling the air flow after the application of the laundry are arranged, wherein the method, the air flow outside the treatment chamber and the blower is divided into two parallel parts, of which a first part of the heater and from which the second part flows through the radiator, after which the parts are reunited with each other, the heater and the radiator belonging to a heat pump means, which pumps heat from the radiator to the heater.

In contrast to a paradigm that can be derived from a functional consideration of the drying process, the invention provides that the cooling of the forced air flow to condense out moisture which has been removed from the laundry and the heating of the air flow before the loading of the laundry, around the outlet To facilitate moisture from the laundry at an elevated temperature, not successively, but parallel to each other.

A prerequisite for this is the knowledge according to the invention that in a conventional clothes dryer never even approximately complete dehumidification of the effluent from the laundry to be dried air flow, and that dehumidification to a standard extent can also be achieved if only a part of The air stream flowing out of the laundry is subjected to dehumidification. The invention also takes advantage of the fact that an air flow absorbs the better heat, the moister he is, and thus compensate for the disadvantage of entering a given amount of heat in only part of the total air flow and to bring this part to a correspondingly higher temperature, is compensable.

A great advantage of the invention, however, is that the parallel arrangement and flow through the heater and the radiator makes a substantially doubled flow area for the forced air flow available and thus a resulting in the flow through the arrangement of radiator and heater pressure loss compared to each device described significantly reduced in the prior art; This reduction is also particularly great because the cooler and the heater no longer need to be flowed through one another in addition of their flow resistance.

Preferably, the second branch comprises a separator for removing moisture from the corresponding part of the air flow downstream of the cooler. By means of this separator, moisture that has condensed out of the air stream in the cooler can be removed from the air stream and fed to a suitable collecting container. It is also advantageous to separate the moisture from the reuniting of the parts of the air stream, since the cooled part of the air stream is reheated by the reunification and thereby condensed moisture could be evaporated again.

The treatment chamber of the device is preferably rotatable and in particular designed as a drum for receiving the laundry, wherein the drum is provided on the inside with strip-like drivers. In such a drum, the laundry can be moved and shaken in the beaufschlagendem air flow, which is conducive to a uniform dehumidification of the laundry while largely avoiding wrinkling in the laundry.

According to the invention, the heater and the radiator belong to a heat pump device, in particular a thermoelectrically operable heat pump device, which heat from the Radiator to the heater pumps. In any heat pump, the cooler and the heater form critical and only under consideration of difficult conditions ausleg- and constructible components, which must be placed due to their interaction in the heat pump appropriately expediently close to each other, which in view of the spatial conditions in a conventional dryer to design difficulties can lead. In particular, in a thermoelectrically operable heat pump, the radiator and the heater are inherently spatially adjacent, because they are arranged on two mutually parallel sides of one equipped with the required Peltier elements, more or less flat parallelepiped-shaped switching block. In a conventional clothes dryer, the radiator and the heater are disposed below the treatment chamber; the air flow is directed from a back of the tumble dryer through the treatment chamber to a front side, from there into the space below the treatment chamber and there from the front side back to the back side. This implies that a channel system arranged under the treatment chamber must be folded in an S-shape with a thermoelectric heat pump for guiding the air flow, which requires a particularly long path length for the air flow, and thus a relatively high flow resistance.

Particularly preferably, the heat pump device in the device comprises at least one thermoelectric switch block with a warm side and a cold side, wherein the cold side is integrated into the radiator and the warm side into the heater. Further preferably, the switching block has a plurality of just next to each other and arranged between two heat conducting plates Peltier elements, wherein the cold side and the warm side is formed in each case by a heat conducting plate. In addition, preferably, the cold side and the warm side are each provided with heat-conducting fins in order to improve the heat transfer to the air flow.

Also preferably, the cooler is additionally designed as a heat exchanger for an additional cooling medium and connected to a second channel system for guiding the additional cooling medium. As an additional cooling medium in particular air is provided. The heat exchanger for the additional cooling medium is used, in particular, during a cooling phase provided following the drying of laundry, during which the device, the air flow and the laundry are cooled become. This is advantageous for preventing wrinkles in the laundry, since the higher the temperature of the laundry, the easier it is to form creases.

A particularly preferred apparatus having a thermoelectrically operable heat pump means is characterized by two thermoelectric switch blocks and a radiator divided into two halves connected in parallel with the warm side of each switch block in the heater and the cold side of each switch block integrated into one of the halves. In this way results in a relatively compact design, in which the heater between the thermoelectric switching blocks, and the thermoelectric switching blocks are stacked with the heater between the halves of the radiator. In this design, the heater is particularly well protected against unwanted heat loss. The design offers a particularly low flow resistance for the air flow, has a small footprint and is very well suited for equipping with a cooler, which is additionally designed as described above as a heat exchanger for an additional cooling medium. In this case, the heat exchanger for an additional cooling medium in two halves corresponding to each other, each of which is associated with a corresponding half of the radiator, divided.

The device according to the invention is designed in particular as a household tumble dryer.

A preferred embodiment of the invention provides that the air flow passes after reuniting the parts to the blower, and from the blower to the treatment chamber.

Preferred embodiments of the device according to the invention correspond to preferred embodiments of the method according to the invention, and vice versa.

The above description of the invention and preferred embodiments, wherein the cooler and the heater are each described as the only components of their kind, does not exclude that depending on the purpose and conditions of use, an additional cooling device, an additional heater or a combination of such is used. Reference should again be made to the relevant references in the cited documents of the prior art.

Fig. 1:

ein Funktionsschema einer Vorrichtung zum Trocknen von Waschgut;

Figuren 2, 3 und 4:

verschiedene Ansichten einer thermoelektrisch betreibbaren Wärmepumpeinrichtung zum Einsatz in einer Vorrichtung zum Trocknen von Waschgut;

Fig. 5:

eine Schnittansicht einer Zentraleinheit für eine thermoelektrisch betreibbare Wärmepumpeinrichtung.

Embodiments of the invention are explained below with reference to the drawing. The drawing is executed as a diagram or sketch and in no way to be understood as true-to-scale reproduction of a real embodiment. In detail show:

Fig. 1:

a functional diagram of a device for drying laundry;

FIGS. 2, 3 and 4:

various views of a thermoelectrically operable heat pump device for use in a device for drying laundry;

Fig. 5:

a sectional view of a central unit for a thermoelectrically operable heat pump.

FIG. 1 1 shows a device for drying laundry 1, comprising a substantially closed first channel system 2 for forcibly guiding an air stream 3 impinging on the laundry 1. In the first channel system 2 is a treatment chamber 4 for receiving the laundry 1, a fan 5 for driving the air flow 3 , a heater 6 for heating the air flow 3 before the loading of the laundry 1 and a cooler 7 for cooling the air flow 3 after the loading of the laundry 1 is arranged. In this case, the first channel system 2 is divided outside the treatment chamber 4 and the blower 5 in two parallel branches 8 and 9, which branches 8 and 9 of corresponding parts 20 and 21 of the air flow 3 can be flowed through in parallel. The heater 6 is arranged in a first branch 8, and the cooler 7 in a second branch 9 of these branches. During operation of the device, the fan 5 drives the air flow 3 through the first channel system 2; before the heater 6 and the radiator 7, the air flow 3 divides into two parts 20 and 21, and from these parts 20 or 21, the heater 6 or the radiator 7 are flowed through in parallel. This arrangement with the heater 6 and the radiator 7 has a particularly low flow resistance for the air flow 3. In the second branch 9 follows on the radiator 7, a separator 10, which is intended for the separation of moisture in the radiator 7 from the corresponding part of the Air stream 3 was condensed out. The condensed Moisture can be removed from the separator 10, as indicated by the arrow.

The treatment chamber 4 is a rotatable about the axis 11 drum 4. By the rotation of the drum 4, the laundry 1 is moved in the air stream 3 and additionally shaken to ensure a uniform drying result. To assist in this movement and shaking, the drum 4 may be provided with drivers, not shown. After flowing through the drum 4, the air stream 3 arrives at a lint filter 12 arranged in the first channel system 2, where lint, which the air stream 3 entrains from the laundry 1, is collected to subsequent areas of the channel system 2, in particular the heater 6 or the cooler 7, not to clog.

The heater 6 and the radiator 7 belong to a thermoelectrically operable heat pump device with a central unit 13, which Peltier elements 16, 22, 23, 24 (see. Fig. 5 The hot side 14 forms a functionally essential component of the heater 6, as does the cold side 15 is a functionally essential component of the cooler 7. The central unit 13 may Also referred to as thermoelectric switching block 13, since it is constructed from the aforementioned Peltier elements 16, 22, 23, 24 and additional Wärmeleitkomponenten, as will be described in more detail below.

The FIGS. 2, 3 and 4 show different views of a heat pump device for use in the device according to Fig. 1 , The view according to Fig. 2 is a vertical section perpendicular to a flow direction of the air flow 3; Fig. 3 a view of a vertically oriented side of the device; Fig. 4 an oblique view of the device. In the following description is on the FIGS. 2 to 4 referred to together.

The device comprises two thermoelectric switching blocks 13, which enclose the heater 6 shown here as a channel for a part of the air flow 3 between them. For this purpose, the warm sides 14 designated here by the letter w are facing each other, the cold sides 15 designated by the letter k are the heater 6 away. Each of the cold sides k forms with a second channel system 18, through which an additional cooling medium 19, in particular air, in cross-flow to the air flow 3 can be guided, one half of the cooler 7, wherein these two halves of the heater 6 and the thermoelectric switching blocks 13th between them. In the heaters 6, the halves of the cooler 7 and the halves of the second channel system 18 protrude heat conducting ribs 17 in order to improve the heat transfer between the various channels and the fluids flowing therein. Each half of the radiator 7 forms with the associated half of the second duct system 18, one half of an additional heat exchanger, which can serve to dissipate additional heat from the radiator 7 and thus to increase the cooling effect. In the simplest case, the second channel system 18 is open and includes the necessary channels and a further fan to bring cooling air from the environment of the device to the heat pump device and from there back into the environment.

The heat pump device comprises both branches 8 and 9 (the branch 9 is in turn divided) of the channel system 2 in a compact and by corresponding, parallel to each other flowing parts 20 and 21 of the air flow 3 through-flow unit. Behind this unit, the heated part 20 of the air stream 20 and the cooled part 21 of the air flow 21 are reunited with each other - understood after separation of the condensate accumulated in the cooled air flow 21, as in Fig. 1 indicated.

Fig. 5 shows a vertical section through a thermoelectric switching block 13th

Functionally essential components of the switching block 13 are primarily Peltier elements 16, 22, 23, 24, which heat up at the flow of a current at one end and cool at another end. The corresponding physical effect is called "Peltier effect" or "thermoelectric effect". A Peltier element 16, 22, 23, 24 consists of a plurality of rectangular or columnar half-elements 16, each consisting of one of two materials, the Fig. 5 are indicated by the letters n and p. In particular, bismuth telluride, antimony telluride and bismuth selenide are suitable as the material, in each case in n-type (n) or p-type doped form. Each half-element 16 is soldered on two mutually opposite sides to a printed circuit board 22 (or a conductor track located thereon), a printed circuit board 22 each having two half-elements 16 made of different materials n or p is connected. The arrangement in the present example is such that the half elements 16 are all connected in series, and on both corresponding sides of the plurality of half elements 16 there results an arrangement of printed circuit boards 22, which are arranged overall in one plane. The printed circuit boards 22 are connected to a ceramic plate 24 on both sides of the half elements 16 via an adhesive connector 23, and in this form available as "Peltier elements" on the market. In the presently illustrated arrangement, the ceramic plates 23 are in turn connected via a thermal paste or heat conducting film 25 with a heat conducting plate 14 or 15; The heat-conducting plate 14 forms the warm side 14, the heat-conducting plate 15, the cold side 15 of the heat pump. It should be noted that the in Fig. 5 shown arrangement is to be understood only as an example.

LIST OF REFERENCE NUMBERS

1

laundry

2

First channel system

3

airflow

4

Treatment chamber, drum

5

fan

6

stoker

7

cooler

8th

First branch

9

Second branch

10

separators

11

Axis of the drum

12

lint

13

Heat pump unit, central unit, thermoelectric switch block

14

Warm side, heat conduction plate

15

Cold side, heat conducting plate

16

Peltier element, half element

17

heat conduction

18

Second channel system

19

Additional cooling medium

20

First part (heated) of the air flow

21

Second part (cooled) of the air flow

22

Circuit board, Peltier element

23

Adhesive connector, Peltier element

24

Ceramic plate, Peltier element

25

Thermal paste or thermal foil

Claims (16)

1. Device for acting on laundry items (1) by an air flow (3), comprising a substantially closed first channel system (2) for constrained guidance of the air flow (3), in which first channel system (2) a treatment chamber (4) for receiving the laundry items (1), a fan (5) for driving the air flow (3), a heater (6) for heating the air flow (3) prior to action on the laundry items (1) and a cooler (7) for cooling the air flow (3) after action on the laundry items (1) are arranged, wherein the first channel system (2) has outside the treatment chamber (4) and the fan (5) two branches (8, 9), which are connected in parallel with one another and which can be flowed through in parallel by corresponding parts (20, 21) of the air flow (3), wherein the heater (6) is arranged in a first branch (8) and the cooler (7) in a second branch (9) of these branches (8, 9), characterised in that the heater (6) and the cooler (7) belong to a heat pump device (6, 7, 13, 14, 15).
2. Device according to claim 1, in which the second branch (9) has downstream of the cooler (7) a separator (10) for separating moisture from the corresponding part (21) of the air flow (3).
3. Device according to one of the preceding claims, in which the treatment chamber (4) is rotatable.
4. Device according to any one of the preceding claims, in which the heat pump device (6, 7, 13, 14, 15) is thermoelectrically operable.
5. Device according to claim 4, in which the heat pump device (6, 7, 13, 14, 15) comprises at least one thermoelectric switching block (13) with a hot side (14) and a cold side (15), wherein the cold side (15) is integrated in the cooler (7) and the hot side (14) is integrated in the heater (6).
6. Device according to claim 5, in which the switching block (13) comprises a plurality of planar Peltier elements (16, 22, 23, 24) which are arranged adjacent to one another and between two thermally conductive plates (14, 15), wherein the cold side (15) and the hot side (14) are each formed by a respective thermally conductive plate (14, 15).
7. Device according to one of claims 5 and 6, in which the cold side (15) and the hot side (14) each have thermally conductive ribs (17).
8. Device according to any one of claims 5 to 7, in which the cooler (7) is additionally constructed as a heat exchanger (7) for an additional cooling medium (19) and is connected with a second channel system (18) for conducting the additional cooling medium (19).
9. Device according to claim 8, in which air is provided as additional cooling medium (19).
10. Device according to any one of claims 5 to 9, in which the heat pump device (6, 7, 13, 14, 15) comprises two thermoelectric switching blocks (13) and in which the cooler (7) has two halves (7) connected in parallel with one another, wherein the hot side (14) of each switching block (13) is integrated in the heater (6) and wherein the cold side (15) of each switching block (13) is integrated in one of the halves (7).
11. Device according to any one of the preceding claims, which is constructed as a domestic laundry dryer.
12. Method of acting on laundry items (1) by an air flow (3) constrainedly guided in a substantially closed first channel system (2), in which first channel system (2) a treatment chamber (4) for receiving the laundry items (1), a fan (5) for driving the air flow (3), a heater (6) for heating the air flow (4) prior to action on the laundry items (1) and a cooler (7) for cooling the air flow (3) after action on the laundry items (1) are arranged, wherein the air flow (3) is divided up outside the treatment chamber (4) and the fan (5) into two parts (20, 21) conducted in parallel to one another, of which a first part (20) flows through the heater (6) and the second part (21) flows through the cooler (7), after which the parts (20, 21) are combined with one another again, characterised in that the heater (6) and the cooler (7) belong to a heat pump device (6, 7, 13, 14, 15) which pumps heat from the cooler (7) to the heater (6).
13. Method according to claim 12, in which the air flow (3) after reunification of the parts (20, 21) passes to the fan (5) and from the fan (5) to the treatment chamber (4).
14. Method according to one of claims 12 and 13, in which moisture condensed from the second part (21) is separated out before it is recombined with the first part (20).
15. Method according to any one of claims 12 to 14, in which an additional heat exchange between the second part (21) and an addition cooling medium (19) takes place at least periodically in the cooler (7).
16. Method according to any one of claims 12 to 15, in which the laundry items (1) are dried.

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