DE102022208980A1 - Process air duct and laundry treatment device - Google Patents

Abstract

The invention relates to a process air duct (8) for a laundry treatment device (1) for drying laundry, wherein when the process air duct (8) is arranged as intended in the laundry treatment device (1) with the process air duct (8), a process air used for drying laundry is supplied to a process air blower Laundry treatment device (1) can be supplied, the process air duct (8) having a process air outlet (9) which can be connected to the process air blower and an outlet chamber (12) upstream of the process air outlet (9), the outlet chamber (12) having a ring segment-shaped design, coaxial with the process air outlet (9) arranged chamber wall (13). In order to reduce energy consumption and noise generation of the laundry treatment device (1), at least one air guide element (15, 19) pointing towards the process air outlet (9) is arranged between the chamber wall (13) and the process air outlet (9).

Description

The invention relates to a process air duct for a laundry treatment device for drying laundry, wherein when the process air duct is properly arranged in the laundry treatment device with the process air duct, a process air used for drying laundry can be fed to a process air blower of the laundry treatment device, the process air duct having a process air outlet and a process air outlet that can be connected to the process air blower has an outlet chamber upstream of the process air outlet, wherein the outlet chamber has a chamber wall designed in the shape of a ring segment and arranged coaxially to the process air outlet. In addition, the invention relates to a laundry treatment device for drying laundry, having a process air duct and a process air blower connected downstream of the process air duct with respect to a flow of process air through the process air duct.

Laundry treatment devices can be designed as dryers or washer-dryers in order to be able to dry laundry. In order to reduce energy consumption associated with a drying process, such a laundry treatment device can be equipped with a heat pump with which heat can be recovered from process air used to dry laundry and used again to heat process air used to dry laundry. A section of a process air circuit of the laundry treatment device, in which a condenser of the heat pump is arranged, is usually connected via a process air duct to a process air blower of the process air circuit, with which the process air can be circulated in the process air circuit during a drying process.

The flow field that arises during a drying process on a suction side of the process air blower in an outlet chamber of the process air duct immediately upstream of the process air blower is conventionally very complex and includes dominant flow separation zones in the vicinity of the process air outlet of the process air duct leading to the process air blower. This complexity is largely due to the conventional geometry of the outlet chamber, in particular to the circular disk-shaped shape of the outlet chamber, whereby the process air flowing into the outlet chamber is stimulated to form a flow circulation. This flow recirculation rotates against the direction of rotation of an impeller of the process air blower, which leads to a higher power consumption of the process air blower.

In addition, current heat pump dryers may have unstable airflow performance and thus different performance conditions resulting from a sudden change in flow rate (operating point), which in turn leads to higher power consumption and higher noise levels.

DE 10 2012 012 511 A1 relates to a blower for use in the air flow process of a household appliance. The blower has a housing surrounding the fan wheel with an inflow cover and inflow opening, which has a dissipative recirculation area in the suction area of the gaseous medium flowing into the fan wheel, which can lead to a reduction in the efficiency of the delivery of the medium and to increased noise. In addition, the blower has a device for reducing the effect of the dissipative recirculation area. The inflow cover has at least one return flow opening directed towards the inflow side of the inflow cover in the area of the lowest specific volume flow within the dissipative recirculation area.

An object of the invention is to reduce energy consumption and noise generation of a laundry treatment device.

This task is solved by the independent patent claims. Advantageous embodiments are shown in the following description, the dependent patent claims and the figures, whereby these embodiments, taken alone or in various combinations of at least two of these embodiments with one another, can represent a further, in particular preferred or advantageous, aspect of the invention.

A process air duct according to the invention for a laundry treatment device for drying laundry, which, when the process air duct is properly arranged in the laundry treatment device with the process air duct, can be used to supply process air used for drying laundry to a process air blower of the laundry treatment device, has a process air outlet that can be connected to the process air blower and an outlet chamber upstream of the process air outlet on, wherein the outlet chamber has a ring segment-shaped chamber wall arranged coaxially to the process air outlet and at least one air guide element pointing towards the process air outlet is arranged between the chamber wall and the process air outlet.

According to the invention, with the at least one air guide element, a part of the process air impinging on it within the outlet chamber The process air flow given in the channel is slowed down so that no conventional process air circulation occurs in the outlet chamber. Instead, the part of the process air flow in the process air duct that hits the air guide element is redirected in the direction of the process air outlet of the process air duct in order to be able to flow directly to the process air blower. Overall, the invention achieves more stable process air flow conditions with higher efficiency, in particular a reduction in power consumption with the same process air throughput and pressure. In addition, the invention significantly improves the acoustic comfort of a laundry treatment device.

Advantageously, the air guide element is arranged to run essentially radially towards the process air outlet.

Even more advantageously, the air guiding element is arranged on an inner lateral surface of the chamber wall. Such a design can provide better mechanical stability for the air guide element as well as for the chamber wall.

The air guide element can be monolithically connected to the rest of the process air duct. The air guiding element can additionally be connected to a side wall section of the process air duct that has the process air outlet. The process air duct can also have two or more air guide elements, in particular of different or identical design.

The process air flowing through the process air duct flows via the process air outlet to the process air blower. The process air outlet can, for example, have a circular or elliptical cross-sectional area or be designed as a regular polygon. The outlet chamber upstream of the process air outlet can, for example, be designed in the shape of a circular disk and thus be arranged coaxially to a central axis of the process air outlet. Part of this outlet chamber is closed radially on the outside by the chamber wall, which is designed in the shape of a ring segment and is arranged coaxially to the process air outlet.

The process air duct can form a section of a process air circuit of a laundry treatment device. If the process air duct is arranged correctly in the laundry treatment device, process air used for drying laundry can be supplied to a process air blower of the laundry treatment device using the process air duct, for which purpose a section of the process air circuit, in which a condenser of the heat pump is arranged, is connected to the process air blower of the process air circuit via the process air duct can be.

According to an advantageous embodiment, the air guiding element is lamellar or block-shaped. Similar good results within the meaning of the invention can be achieved with both configurations of the air guiding element. The lamella-shaped air guide element can, for example, be designed to be planar, curved, perforated, corrugated or the like. The block-shaped air guide element can, for example, have a parabolic, semicircular or semi-elliptical cross-sectional area that is oriented perpendicular to the chamber wall. Alternatively, the block-shaped air guide element can have a polygonal, in particular triangular, square or trapezoidal, cross-sectional area.

According to a further advantageous embodiment, the air guide element is arranged on a section of the chamber wall opposite an inflow section of the outlet chamber, via which the process air flows into the outlet chamber, with respect to an axis of symmetry of the process air outlet. This positioning of the air guiding element has been shown to be particularly effective in studies. The air guiding element can be arranged on the chamber wall, for example, in an area of the chamber wall that extends, for example, over 180°. If the process air duct is properly arranged in a laundry treatment device, this area of the chamber wall can be arranged, for example, on a side of a vertical plane facing away from the inflow section, which contains the central axis of the process air outlet.

According to a further advantageous embodiment, the air guide element is arranged at the height of the process air outlet when the process air duct is arranged in the laundry treatment device as intended. Studies have shown that the closer the air guide element comes to the height of the process air outlet, the greater the effectiveness of the air guide element. The height of the process air outlet is understood to mean the geodetic height of the process air outlet when the process air duct is arranged as intended in a laundry treatment device.

According to a further advantageous embodiment, the air guiding element extends from the chamber wall to the process air outlet. The radial dimensioning of the air guide element must be chosen so that at least a radially outer part of the process air flowing into the outlet chamber is braked and redirected with the air guide element.

According to a further advantageous embodiment, the process air duct has at least one further air guiding element arranged in a range of 20° to 180° in the direction of a lower region of the outlet chamber, circumferentially offset from the air guiding element on the inner lateral surface of the chamber wall. This allows the effectiveness of the invention to be further increased. The air-guiding element can be arranged, for example, at the level of the process air outlet, while the further air-guiding element can be arranged, for example, 90° downwards from the air-guiding element. The two air guiding elements can, for example, also be arranged offset from one another by 120°.

A laundry treatment device according to the invention for drying laundry has a process air duct and a process air blower connected downstream of the process air duct with respect to a flow of process air through the process air duct, the process air duct being designed according to one of the above-mentioned embodiments or a combination of at least two of these embodiments with one another.

The advantages mentioned above with regard to the process air duct are associated with the laundry treatment device. The laundry treatment device can be designed as a front loader. The laundry treatment device can be a dryer or a washer-dryer.

• 1. eine schematische Darstellung eines Abschnitts eines Prozessluftkreislaufs eines Ausführungsbeispiels für ein erfindungsgemäßes Wäschebehandlungsgerät;
• 2. eine schematisch und perspektivische Detaildarstellung des in 1 gezeigten Prozessluftkanals;
• 3. eine schematisch und perspektivische Detaildarstellung eines Abschnitts eines weiteren Ausführungsbeispiels für einen erfindungsgemäßen Prozessluftkanal
• 4. eine schematisch und perspektivische Detaildarstellung eines Abschnitts eines weiteren Ausführungsbeispiels für einen erfindungsgemäßen Prozessluftkanal; und
• 5. eine weiteren schematisch und perspektivische Detaildarstellung eines Abschnitts des Ausführungsbeispiels aus 4.

The invention is explained below by way of example with reference to the attached figures using preferred embodiments. It shows:

• 1 . a schematic representation of a section of a process air circuit of an exemplary embodiment of a laundry treatment device according to the invention;
• 2 . a schematic and perspective detailed representation of the in 1 process air duct shown;
• 3 . a schematic and perspective detailed representation of a section of a further exemplary embodiment for a process air duct according to the invention
• 4 . a schematic and perspective detailed representation of a section of a further exemplary embodiment for a process air duct according to the invention; and
• 5 . a further schematic and perspective detailed representation of a section of the exemplary embodiment 4 .

In the figures, identical or functionally identical components are provided with the same reference numbers. Repeated description of these components may be omitted.

1 shows a schematic representation of a section of a process air circuit of an exemplary embodiment of a laundry treatment device 1 according to the invention for drying laundry. Of the laundry treatment device 1, only a section of a process air circuit 2 is shown, within which process air is circulated during a drying process according to the arrows P.

The process air circuit 2 has a section 3 which is connected to a drying chamber, not shown, of the laundry treatment device, in which a laundry drum, not shown, is rotatably mounted. Furthermore, the process air circuit 2 has a section 4 connected to the section 3, on which an evaporator 5 and a condenser 6 of a heat pump 7 of the laundry treatment device 1 are arranged. In addition, the process air circuit 2 has a process air duct 8 connected to the section 4 and a process air blower, not shown, which is connected downstream of the process air duct 8 with respect to the flow of the process air through the process air duct 8 indicated by the arrow P. The structure of the process air duct 8 is explained below using 2 described.

2 shows a schematic and perspective detailed representation of the in 1 shown process air duct 8. The process air duct 8 has a circular process air outlet 9 which can be connected to the process air blower (not shown) and is formed on a side wall 11, a rotor 10 of the process air blower being shown. An axis of symmetry 16 of the process air outlet 9 is shown, which is perpendicular to an opening plane of the process air outlet 9 and, in the exemplary embodiment, is identical to an axis of rotation of the rotor 10.

Furthermore, the process air duct 8 has an outlet chamber 12 located upstream of the process air outlet 9. The outlet chamber 12 has a chamber wall 13 designed in the shape of a ring segment and arranged coaxially with the process air outlet 9. In the 2 the process air duct 8 is shown such that the process air would flow from a process space (not shown) from left to right through an inflow section into the outlet chamber 12 and would leave the same to the rear through the process air outlet 9.

On an inner lateral surface 14 of the chamber wall 13, a radially inwardly extending, lamella-shaped air guide element 15 is arranged. The air guide element 15 is on one Section of the chamber wall 13 arranged, which corresponds to the in. with respect to the axis of symmetry 16 of the process air outlet 9 2 , opposite the inflow section located to the left of the outlet chamber 12. In particular, the air guiding element 15 is arranged at the level of the process air outlet 9, i.e. laterally next to the process air outlet 9. The air guiding element 15 extends from the chamber wall 13 to the process air outlet 9, or to the edge of the circular opening of the process air outlet 9.

In addition, the process air duct 8 has a further air guiding element 17. This further air-guiding element is offset by 90° from the air-guiding element 15 on the circumference of the inner lateral surface 14 of the chamber wall 13, namely in the direction of a lower region of the outlet chamber 12. The further air-guiding element 17 is also located on a section of the chamber wall 13 with respect to the axis of symmetry 16 of the process air outlet 9 arranged, which is located opposite the inflow section of the outlet chamber 12. The further air guiding element 17 also extends from the chamber wall 13 to the process air outlet 9. However, the further air guiding element 17 is not arranged at the level of the process air outlet 9, but below the process air outlet 9.

3 shows a schematic and perspective detailed representation of a section of a further exemplary embodiment for a process air duct 18 according to the invention for a laundry treatment device, not shown, for drying laundry.

The process air duct 18 essentially differs from that in the 1 and 2 shown embodiment that the two air guide elements 19 and 20 are block-shaped. To avoid repetition, reference is made to the above description 1 and 2 referred.

The 4 and 5 show a schematic and perspective detailed representation of a section of a further exemplary embodiment for a process air duct 28 according to the invention for a laundry treatment device, not shown, for drying laundry.

The process air duct 28 essentially differs from that in the 1 and 2 shown embodiment, that the air guide elements 25 are designed in the form of ribs which extend between the chamber wall 13 and the process air outlet 9 to such an extent that they protrude over the opening of the process air outlet. At the end facing away from the chamber wall, the ribs are supported on a stabilizing ring 26, which is here arranged concentrically to the axis of rotation of the rotor (not shown). This results in a spider-like air guidance structure that combines advantageous air guidance in the sense of the invention and good mechanical stability.

Here too, to avoid repetition, reference is made to the above description 1 and 2 referred.

List of reference symbols:

1

Laundry treatment device

2

Process air circuit

3

Section of 2

4

Section of 2

5

Evaporator

6

liquefier

7

Heat pump

8th

Process air duct

9

Process air outlet

10

rotor

11

Side wall of 8

12

outlet chamber

13

Chamber wall

14

Inner surface area of 13

15

Air guide element

16

Axis of symmetry of 9

17

another air guide element

18

Process air duct

19

Air guide element

20

another air guide element

25

Air control elements

26

Stabilization ring

28

Process air duct

P

Arrow (process air flow)

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102012012511 A1 [0005]

Claims (8)

Process air duct (8, 18) for a laundry treatment device (1) for drying laundry, wherein when the process air duct (8, 18) is arranged as intended in the laundry treatment device (1) with the process air duct (8, 18), process air used for drying laundry is provided Process air blower of the laundry treatment device (1) can be supplied, the process air duct (8, 18) having a process air outlet (9) which can be connected to the process air blower and an outlet chamber (12) upstream of the process air outlet (9), the outlet chamber (12) having a ring segment-shaped, Has a chamber wall (13) arranged coaxially to the process air outlet (9), characterized in that at least one air guide element (15, 19) pointing towards the process air outlet (9) is arranged between the chamber wall (13) and the process air outlet (9). Process air duct (8, 18). Claim 1 , characterized in that the air guide element (15, 19) is arranged to run essentially radially towards the process air outlet (9). Process air duct (8, 18). Claim 1 or 2 , characterized in that the air guide element (15, 19) is arranged on an inner surface (14) of the chamber wall (13). Process air duct (8, 18) according to one of the preceding claims, characterized in that the air guide element (15, 19) is lamellar or block-shaped. Process air duct (8, 18) according to one of the preceding claims, characterized in that the air guide element (15, 19) is located on a section of the chamber wall opposite an inflow section of the outlet chamber (12) with respect to an axis of symmetry (16) of the process air outlet (9). (13) is arranged. Process air duct (8, 18) according to one of the preceding claims, characterized in that the air guide element (15, 19) extends from the chamber wall (13) to the process air outlet (9). Process air duct (8, 18) according to one of the preceding claims, characterized by at least one circumferentially offset from the air guide element (15, 19) on the inner lateral surface (14) in a range of 20° to 180° in the direction of a lower region of the outlet chamber (12). another air guide element (17, 20) arranged on the chamber wall (13). Laundry treatment device (1) for drying laundry, comprising a process air duct (8, 18) and a process air blower connected downstream of the process air duct (8, 18) with respect to a flow of process air through the process air duct (8, 18), characterized in that the process air duct (8 , 18) according to one of the Claims 1 until 7 is trained.