EP2886699B1 - Drum for drying laundry, and laundry drying machine provided with same - Google Patents

Description

The invention relates to a drum for drying items of laundry in a tumble dryer, comprising a cylinder axis, a cylindrical shell with respect to the cylinder axis, a circular rear end face oriented substantially vertically with respect to the cylinder axis and an annular front end bottom oriented substantially perpendicular to the cylinder axis and at least a driver to take along laundry on rotation of the drum about the cylinder axis, which is arranged on an inner side of the shell and at an acute angle to the cylinder axis.

The invention also relates to a tumble dryer having such a drum.

Such a drum and such a tumble dryer are each disclosed and illustrated in the drawing U.S. Patent 2,670,549 and the U.S. Patent 5,463,821 , In each of these documents, a laundry washer formed as a laundry dryer is described which has a drum rotatable about a horizontal plane. On the inside of the shell of this drum several parallel to the cylinder axis aligned and punched drivers are attached. Process air for receiving moisture from laundry items to be dried in the drum passes through the drivers into the interior of the drum and to the laundry items, and is discharged from the drum through the opening in the annular front face. According to U.S. Patent 5,463,821 Magnetrons are mounted in the drivers, by means of which the laundry to be dried is heated with microwaves. The process air flowing through the drivers also serves to cool these magnetrons.

From the U.S. Patent 6,324,771 is a clothes dryer of the above type, in which in addition to the drivers of the cylindrical shell of the drum is perforated. The largest part of the process air used for drying the laundry is to flow through the jacket of the drum away from the driver. Through the driver through but a bypass is formed by the regular operation, a small part of the process air flow, but also for deriving process air is available when the openings in the jacket are hidden away from the driver by laundry. In this way, a minimum flow of process air through the drum should be ensured even at high loading of the drum.

From the EP 1 190 135 B1 is a front-loadable washing machine with a rotatable drum out, with washing items to be washed are absorbed by the drum. The drum has a cylinder axis which is slightly inclined with respect to a horizontal plane. In the drum drivers are attached, each of which is hollow and arranged to receive washing liquid in the lower part of the drum and to let them flow out again in the upper part of the drum. For this purpose, each driver has corresponding holes, which are arranged in the interior of the drum facing surface.

Also the DE 10 2011 006 697 A1 discloses a Wäschepflegemaschine with a drum and arranged therein drivers. The drivers are made of an elastic and elastic material. Upon contact with laundry items to be treated in the rotating drum, these drivers may deform. A development of such systems results from the WO 2013/050347 A1 , Accordingly, the deformation of the driver takes place in such a way that walls of the driver deform under pressure in a direction against this pressurization.

The invention is therefore based, in particular, on the object of further developing the known drum and the known tumble dryer in such a way that an improvement in the flow through the drum with process air and an improvement in the absorption and removal of moisture from laundry items in the drum are achieved.

To solve this particular problem, a drum and a tumble dryer according to the respective independent claim. Preferred and advantageous developments of the invention will become apparent from the dependent claims, the following description and the accompanying drawings. preferred Further developments of the drum according to the invention always correspond to preferred developments of the tumble dryer according to the invention and vice versa, and this even if it is not explicitly stated herein.

To solve this object, in particular, a drum for drying laundry in a tumble dryer, with a cylinder axis, a cylindrical axis with respect to the cylinder shell, with respect to the cylinder axis substantially vertically aligned, circular rear end floor and with respect to the cylinder axis substantially vertically aligned annular front forehead bottom and at least one driver for taking along laundry on rotation of the drum about the cylinder axis, which is arranged on an inner side of the shell and at an acute angle to the cylinder axis, wherein drum further comprises the driver has an open in an interior of the drum hollow lattice structure, which has an interior facing surface which is at least 50% open.

To solve this particular task is therefore also given a clothes dryer for drying laundry in a drum with a cylinder axis, a cylindrical axis with respect to the cylinder shell, a respect to the cylinder axis substantially vertically aligned, circular rear end floor and a cylinder axis with respect to the substantially vertically aligned annular front forehead bottom and at least one driver for taking along laundry on rotation of the drum about the cylinder axis, which is arranged on an inner side of the shell and at an acute angle to the cylinder axis, wherein furthermore the driver has an open in an interior of the drum hollow lattice structure, the one the interior facing surface which is at least 50% open.

According to the invention, at least one driver is provided in the drum, which is constructed such that it on the one hand the function of lifting laundry items when turning the drum, and on the other hand as good as possible and with the lowest possible flow resistance of process air, which flows around the laundry is flowed through , Thus, absorption and removal of moisture from the laundry items can be improved.

According to the invention it is provided that the grid structure of the driver has a surface facing the interior, which is at least 50% open. This ensures a particularly low flow resistance for through-flowing process air, but there is also room for enough material to represent the grid structure with sufficient strength.

The interior of the drum is closed along the cylinder axis by a circular rear end floor and by an annular front end floor to hold the laundry items in the interior. Each forehead bottom may be fixedly connected to the shell so as to rotate together with it, or be separate from the shell. In such case, it may be necessary to provide a seal between such a face and the jacket which prevents unwanted leakage of process air through an open gap between the jacket and the face. Such measures are familiar to the relevant specialist. The foreheads are arranged basically perpendicular to the cylinder axis, but this does not mean that they would have to be flat in practice. For example, to achieve sufficient drum strength, they could be obtuse conical and / or textured. The back forehead is circular, the front forehead is circular. In this way, the laundry items can be introduced through the front end floor into the drum or removed from it. During operation of the drum, the opening in the front forehead bottom is closed by a door, not shown.

The jacket can be smooth or structured, in particular by embossing structures. It can also be perforated to allow process air or, in the application in a washing machine, washing liquid. Also, a forehead bottom can be perforated, for example, to let process air into the drum or lead out of the drum.

The purpose of the drum according to the invention, namely the drying of items of laundry, does not exclude the use of the drum according to the invention in a laundry care machine which is not or not only intended for drying laundry items. The laundry care machine could be a so-called washer dryer in which laundry items can be both washed and dried. In this case, the invention would be the same when drying the laundry as usable in a tumble dryer. The laundry care machine could also be a washing machine for washing laundry items. In such a case, the good flow-through properties of the driver to be provided according to the invention can be used to bring washing liquid such as wash liquor, rinse liquor or simple water in an improved manner, in particular more intensively than hitherto possible, into contact with laundry items to be treated. For receiving washing liquid and lifting the washing liquid, so that it can flow from the top of the laundry, it might be appropriate to provide a corresponding scooping device inside the driver or under the driver.

In a further development of the invention, it is provided to design the surface such that it is at least 70% open. This ensures a particularly low flow resistance for throughflowing process air, but there is still room for enough material to present the grid structure with sufficient strength. By suitable choice of the material from which the driver consists (see also the following comments on other training, which can be very well combined with the training described here), this can be achieved.

In another embodiment of the invention it is provided that the driver is hollow. In this way, process air for drying or washing liquid for washing or rinsing can freely flow through the driver, resulting in a further improvement of such flow.

According to a further development of the invention it is provided that the driver consists of a thermoplastic material. Thus, the driver can be produced in the context of well-known and proven for the production of components of Wäschepflegemaschinen and proven method, in particular by injection molding. Also, such a driver can be manufactured and purchased at low cost.

According to yet another embodiment of the invention, according to current practice rather unusual material metal is used for the driver. In this case, the driver can be made in particular of an expanded metal or a wire mesh. When fabricating the driver made of expanded metal this may possibly as an integral part of the usual practice also made of metal shell of the drum as so-called "retracted driver" are produced by, for example, a flat sheet metal stamped in the region of the driver and / or slotted and then brought by deep drawing in the shape of the driver. When manufactured from a wire mesh can be particularly large when using correspondingly strong and stiff wire for the production of the driver, the open portion of the surface; for preferred proportions see corresponding comments above.

According to yet another embodiment of the invention, the at least one driver belongs to an arrangement with a plurality of mutually identical drivers. In this case, the plurality of carriers are preferably arranged symmetrically with respect to the cylinder axis on the inside. In particular, two or three drivers may be present, these being the only carriers present in the drum.

According to yet another embodiment of the invention, the cylinder axis of the drum is aligned in the tumble dryer in an approximately horizontal plane. As a result, when the drum is rotated, the items of laundry contained in it are lifted somewhat upwards by the driver or the carriers and then fall off the carriers. As a result, the laundry items are moved through the process air stream and the process air is allowed to flow along all sides and regions of the laundry items. This causes a particularly uniform drying. This effect is achieved not only when the cylinder axis is aligned exactly horizontally, but also when it forms a small angle with the horizontal. This angle is preferably not more than 45 °, more preferably less than 30 °.

It should again be noted that the drum according to the invention can also be advantageously used in a laundry care machine for washing laundry, wherein a preferred arrangement of the cylinder axis as set out in the previous paragraph is likewise advantageous. When washing, the lifting and dropping of laundry items causes them to be mechanically processed, effectively assisting the removal of dirt and other contaminants. Also, an improved distribution of the washing liquid can thereby assist.

According to yet another embodiment of the invention, the tumble dryer on a process air cycle, in which process air can be guided by heating and cooling through the drum to absorb moisture from the laundry and dissipate, wherein a heat pump is provided for heating and cooling the process air. A clothes dryer with a heat pump is characterized by a particularly low energy consumption with the same drying performance as a conventional dryer with heater and radiator, because the heat must be removed to eliminate moisture contained in the process air flow, collected in the heat pump and fed back to the process air flow can. However, a heat pump in a dryer often achieves only a lower maximum temperature in the process air flow compared to a conventional electric heater, whereby the absorption of moisture can also only take place to a reduced extent. In this context, the benefits that can provide the drum according to the invention, a special effect and importance.

Figur 1

einen Wäschetrockner mit einem Mitnehmer mit einer Gitterstruktur;

Figur 2

einen Mitnehmer; und

Figur 3

einen Mitnehmer, angebracht auf einem Mantel.

Preferred embodiments of the invention are illustrated in the figures of the accompanying drawing and are explained below. Show it:

FIG. 1

a clothes dryer with a driver with a grid structure;

FIG. 2

a driver; and

FIG. 3

a driver, mounted on a coat.

FIG. 1 shows a clothes dryer 1, that is only its functionally and relevant to the present explanations components. Not shown are a housing, a door with which the tumble dryer 1 is closed, a control device that controls the operation of the tumble dryer 1, any necessary sensors and drive devices. For practical embodiments of the tumble dryer 1, however, such components are necessary and are provided and attached within the scope of the knowledge of the relevant professionals.

The tumble dryer 1 is used for drying damp laundry items 2, which are located in a drum 3 which is rotatable about a cylinder axis 4. The drum 3 is made in accordance with common practice of sheet metal and has a cylinder barrel 4 with respect to the cylindrical sheath 5, a rear end floor 6 and a front end floor 7. The foreheads 6 and 7 are basically arranged perpendicular to the cylinder axis 4, but this does not mean that they would have to be flat in practice. For example, to achieve sufficient strength of the drum 3, they could be obtuse conical and / or structured. The rear end floor 6 is circular, the front end floor 7 circular. In this way, the laundry items 2 can be introduced through the front end floor 7 into the drum 3 or removed from it. During operation of the tumble dryer 1, the opening in the front end floor 7 is closed by a door, not shown.

A driver 8 can be seen, which consists of a wire mesh. Attached is this driver 8 with two other, same and not shown for clarity, on an inner side 9 of the shell 5, and the interior 10 of the drum 3 faces. The wire mesh of the driver 8 forms a lattice structure 11, which defines a the interior 10 facing surface 12 which is open to the interior 10 to a very large proportion of at least 50%, specifically even more than 70%. The driver 8 is hollow inside. As a result, process air, which flows through the interior 10 for drying the laundry items 2, can flow through the driver 8. It can therefore reach all sides and areas of the laundry particularly well, which promotes a particularly fast and uniform, especially so particularly effective drying of the laundry items 2.

The process air, which is to dry the laundry items 2, flows in a substantially self-contained process air circuit 13, which is shown schematically, being driven by a fan 14. The fan 14 promotes the process air after prior heating in the drum 3 into where it flows around the laundry items 2 and absorbs moisture from them. With the process air, this moisture first passes into a lint filter 15, where finely divided fibers and particles, which has detached the process air from the laundry items 2, are collected. Subsequently, the process air enters a heat pump 16, 17, 18, 19, 20, where it is first cooled and then heated again.

The heat pump 16, 17, 18, 19, 20 comprises a self-contained refrigerant circuit 16, in which circulates a cyclically liquefied and vaporized refrigerant. The refrigerant is driven by a compressor 17, which it in gaseous Condition and low temperature flows. In the compressor 17, the refrigerant is compressed and heated (substantially adiabatically). It then arrives at a condenser 18, namely a heat exchanger, in which it gives off heat to the likewise flowing process air. The refrigerant is liquefied. In the liquid state, it flows through an expansion device 19, for example a capillary, a diaphragm or a valve, where it is expanded (essentially isenthalp). This reduces its internal pressure and temperature and turns it into a mixture of liquid and gas. In this state, it passes into the evaporator 20, a heat exchanger, which is also traversed by the process air. There, the refrigerant absorbs heat from the process air, so that it cools and condenses the entrained moisture. The completely gaseous again in the evaporator 20 refrigerant passes back to the compressor 17 to be re-compressed and to go through his cycle again. In the evaporator 20, the liquid condensate formed in the process air precipitates out of the process air and is collected in a condensate collector 21 for later disposal. The cycle of the process air is thus: From the blower 14 in the drum 3 and to the laundry 2, from there via the lint filter 15 to the evaporator 20, after excretion of the condensate from there to the condenser 18, and the fan 14 back.

FIG. 2 shows an embodiment of a driver 8 with a grid structure 11 in a view from above or from the cylinder axis 4 (see. Fig. 1 ) ago. This grid structure 11 may be formed of an expanded metal or a perforated plate; Also conceivable and practicable would be forming by injection molding of a suitable plastic material. Again, it should be noted that the interior 10 facing surface 12 is closed only to a small extent, but most of the open. The driver 8 is hollow inside and substantially empty, so that you can at least partially detect fasteners 22 for securing the driver 8 on the jacket 5. These fasteners 22 may be tabs with threaded holes or clamps of various types, according to the knowledge of the relevant professionals and the common practice.

While the driver 8 of the FIG. 2 is more or less straight, shows the driver 8 of the FIG. 3 an S-shaped curved shape. The driver 8 is mounted on the inner surface 9 of the shell 5, with fasteners 22 not visible this time are. Also, this driver 8 has a the interior 10 facing surface 12, which is quite predominantly open, and he is also hollow inside. The peculiarity of this driver 8 is that when turning the drum 3 (see. Fig. 1 ) not only lifts the laundry items 2 and drop, but also tells them a pulse parallel to the cylinder axis 4. This leads to a further improved mixing of the laundry items 2 with each other, and to a further homogenization of the drying of the laundry items. 2

A special feature of the drum 3 taught here for the first time and of the tumble dryer 1 taught here for the first time is accordingly the driver 8, which is now also explained in detail and constructed in such a way that on the one hand it fulfills the function of lifting laundry items 2 when rotating the drum 3, and on the other hand, as good as possible and with the lowest possible flow resistance of process air, which flows around the laundry items 2, can be flowed through.

LIST OF REFERENCE NUMBERS

1

clothes dryer

2

laundry

3

drum

4

cylinder axis

5

coat

6

Back forehead

7

Front forehead

8th

takeaway

9

Inside of the coat

10

Interior of the drum

11

lattice structure

12

Surface on the driver

13

Process air circuit

14

fan

15

lint filter

16

Refrigerant circulation

17

compressor

18

condenser

19

expansion element

20

Evaporator

21

condensate collector

22

fastening device

Claims (12)

1. Drum (3) for drying laundry items (2) in a tumble dryer (1), with a cylindrical axis (4), a jacket (5) which is cylindrical with respect to the cylindrical axis (4), a circular rear end wall (6) aligned essentially perpendicularly with respect to the cylindrical axis (4) and a front end wall (7) in the shape of a circular ring aligned essentially perpendicularly with respect to the cylindrical axis (4), as well as at least one agitator (8) for agitating laundry items (2) while the drum (3) rotates about the cylindrical axis (4), which is arranged on an inner side (9) of the jacket (5) and at an acute angle to the cylindrical axis (4), characterised in that the agitator (8) has a hollow frame structure (11) which is open into an interior (10) of the drum (3), which frame structure (11) has a surface (12) which faces towards the interior (10) and is at least 50% open.
2. Drum (3) according to claim 1, in which the surface (12) is at least 70% open.
3. Drum (3) according to one of the preceding claims, in which the agitator (8) is hollow.
4. Drum (3) according to one of the preceding claims, in which the agitator (8) consists of a thermoplastic material.
5. Drum (3) according to one of claims 1 to 3, in which the agitator (8) consists of a metal.
6. Drum (3) according to claim 5, in which the agitator (8) consists of an expanded metal.
7. Drum (3) according to claim 5, in which the agitator (8) consists of a wire frame.
8. Drum (3) according to one of the preceding claims, in which the at least one agitator (8) belongs to an arrangement with a plurality of agitators (8) which are identical to one another.
9. Drum according to claim 8, in which the plurality of agitators (8) is arranged symmetrically on the inner side (9) with respect to the cylindrical axis (4).
10. Tumble dryer (1) for drying laundry items (2) in a drum (3) according to claim 1.
11. Tumble dryer (1) according to claim 10, in which the cylindrical axis (4) is aligned in an approximately horizontal plane.
12. Tumble dryer (1) according to one of claims 10 and 11, which has a process air circuit (13), in which process air can be guided through the drum (3) while being heated and cooled, in order to absorb and discharge moisture from the laundry items (2), wherein a heat pump (16, 17, 18, 19, 20) is provided to heat and cool the process air.

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