EP2177656A1 - Drum for a laundry dryer - Google Patents

Abstract

The drum (3) has a cylinder or truncated cone shaped shell (19) including a structure on a surface, where the structure is provided with individual convex segments (22). The convex segments have different sizes such that the structure forms a curved pattern on the surface of the shell, where the curved pattern is designed in a swing S-shape. The pattern is extended in a circumferential direction (U). The pattern generates partially differential flows and/or swirls of drying air for providing different intensive air cushions at the shell.

Description

The invention relates to a drum for a tumble dryer, in which the drum can be rotatably mounted on a horizontal or inclined axis, comprising a cylindrical or frusto-conical shell, which comprises on its surface a structure consisting of individual curved segments.

For drying wet or damp laundry items, there are known dryers with a rotatable drum, through which a heated air stream flows in order to dry the laundry located therein. Here, the wet laundry items are swirled around by the drum rotation, so that they are well flowed through by the drying air, whereby the laundry is deprived of moisture. For this purpose, the drum usually has driving ribs in order to lift the laundry items in the circumferential direction, wherein they detach in the upper region due to their gravity from the drum shell and impinge on the drum shell down. When tumbling or tumbling inside the drum, the laundry is most effectively exposed to the drying air.

From the EP 1 293 594 B1 a drum for a tumble dryer is known, which has a structure of outwardly directed, to the drum outer bulges for improved entrainment. This additionally protects the laundry items, as they can slide on a bubble, caused by partial Luftverwirbelungen in the area of the bulges, very low friction along. The bulges are here uniformly structured, so that the laundry movement is caused in the circumferential direction of the drum. In this case, it may happen that the laundry pieces curl together in a ring, so that there is a rolling movement with less mixing with the drying air.

The invention is therefore based on the object to provide a drum for a tumble dryer with buckles, in which the mixing of the laundry with the drying air is improved in a simple manner.

The object is achieved by a drum having the features of claim 1. Advantageous embodiments will become apparent from the following dependent claims.

The main advantage of the drum according to the invention is that an improved movement of the laundry items within the drum is achieved when arranged approximately horizontally or inclined and with a usual speed for the drying process, for example 20 to 70 rpm is rotated. Furthermore, the conservation of the laundry items is maintained or improved, so that premature wear or damage can be avoided.

For this purpose, the drum according to the invention, in particular the drum casing, comprises a structure of curvatures directed towards the drum outer, which consists of individual curved segments. The size of the segments is designed differently such that the structure of the curved segments forms a curved pattern on the jacket. Due to the curved pattern, partially different flows or turbulences of the drying air are caused, as a result of which differently intensive air cushions are formed on the drum shell. As a result, due to the curvature, moving laundry items are moved on or close to the drum shell somewhat in the axial direction or in the direction of an edge of the drum shell, so that the laundry items are moved more strongly within the drum. The so-called roll effect is thereby alleviated, since the laundry items in addition to the circumferential direction now additionally in the axial direction, based on the operating installation position of the drum, moves and / or at least sporadically receive motion pulses in the axial direction. In this case, it is possible to make the otherwise common driving ribs smaller or flatter, since the washing movement is enhanced by the arch structure in the casing. Optionally, the use of driving ribs can be completely dispensed with.

For the formation of the curvature, it is expedient to make the segments arched towards the outside of the drum. As a result, different sized air cushion or additional air turbulence in the area created close to the drum shell, whereby the laundry movement in the axial direction is improved overall.

In an advantageous embodiment, the pattern is S-shaped or S-shaped several times curved. As a result, force impulses or movement impulses are exerted transversely to the circumferential direction in two opposing directions on the laundry casing resting against the drum casing, so that the laundry items reciprocate in the axial direction when the drum is rotated. The directional impulses are also exerted on the items of laundry which impinge on the drum shell during the tumble or slide along it, so that on the whole a seemingly chaotic or chaotic or inhomogeneous movement of the items inside the drum is produced than in the case of a drum with a uniform arch structure.

Overall, it is advantageous that the curved segments are formed of polygons which abut each other with their edge contours, wherein the segments have a length and a width of about 1 to 5 cm. This results in a nearly coherent arch structure, which can thereby exert particularly effective movement impulses on the laundry. The corners of the polygons, in this example honeycombed 6-corner, can be rounded, so that sharp-edged transitions are avoided. The roundings in this embodiment have a radius in the range of 2 to 10 mm.

The height of the bulges is chosen so that they have about the same height and that the height is about 0.1 to 2 mm. As a result, the smaller segments are more curved in relation to their area than the larger segments, based on the base area of the respective individual segment. Thus, a partially different mechanical effect on the laundry is effected, whereby the motion caused by the vault structure movement pulses are enhanced.

In another embodiment, the bulges each have a height which is approximately proportional to the length and width of the surfaces, wherein the height corresponds to about 1/500 to 1/20 of the width or the length of the respective segment. This can be advantageous to avoid exaggerated violent impulses for the laundry and to achieve a gentle laundry treatment.

In order to provide the segments of different sizes, it is expedient for the segments to have at least approximately the same length in the direction of the circumference of the drum and to have a different width in the transverse direction. The size and the arrangement are chosen so that the S-shaped pattern is formed in the circumferential direction of the shell.

In an advantageous development, the segments in the direction of the drum circumference each have a different length, so that the curved or S-shaped pattern is correspondingly formed transversely to the circumferential direction of the jacket. In combination with the circumferential curvature, the undulating pattern includes transverse and longitudinal portions, thereby increasing the inhomogeneity of the structure formed by the segments. As a result, force pulses or movement pulses are introduced in the circumferential direction and transversely to the circumferential direction of the laundry, which further improves the mixing of the laundry with the drying air.

In a further expedient embodiment, the circumferentially extending S-shaped pattern, starting from the approximate centerline of the shell, has a first vertex toward the first end wall and a second vertex toward the second end wall. This ensures that the wave-shaped structure is apparent at least almost over the entire width of the drum shell.

In an advantageous development of the drum shell is divided into at least two sections, wherein in each section in each case an S-shaped pattern or a multiple S-shaped curved pattern of domed segments is arranged. In the areas between the individual sections can be mounted driving ribs, which lift the laundry items as the drum is rotated, so that they peel off again in the upper third and fall down. The driver ribs can be kept very flat, preferably in the range of about 1 to 2 cm with a drum diameter of 50 to 65 cm.

In a further advantageous embodiment, the curved or S-shaped pattern is formed on the jacket in such a way that a curved or S-shaped web results without buckling or arch structure. As a result, an improved guidance of the laundry items along the curved or S-shaped, smooth web is achieved. It is expedient that the web has approximately the width corresponding to the length of a segment in the circumferential direction. Thus, so to speak, a segment width is kept free of bulges, wherein in the S-shaped embodiment of the web starts approximately in the central region or equatorial region of the shell and ends after his arcuate deflections back in the equatorial region.

In an advantageous embodiment, the width of the web varies, wherein the width of the web at the narrowest point in the central region of the drum portion or the drum circumference approximately the length of a segment and at the widest point in the apex region or at the ends of the S-shaped web approximately Length of 1.5 to 2 times a segment corresponds. That is, starting in the equatorial region of the shell of the web is designed to be 1.5 to 2 times wider than in the center region of the web, wherein the center of the web, based on the circumference of the drum shell, is also located in the equatorial region. The arcuate deflections of the web deviate once in the direction of the first end wall and once in the direction of the second end wall of the drum from the equatorial line.

In an advantageous development of the web is provided with additional directed to the drum outer and / or drum interior surfaces, wherein the curved surfaces each have a length in the circumferential direction of the shell of about 0.4 to 0.8 times the length of a nearest segment and a width from about 0.4 to 0.8 times the width of a nearest segment. As a result, the leadership of the coat along sliding laundry in the axial direction or, in the direction of the end walls is further improved.

Fig. 1:

einen Wäschetrockner in einer skizzierten Schnittdarstellung;

Fig. 2:

die Trommel in einer perspektivischen Ansicht und

Fig. 3 bis 7:

den Trommelmantel in einer abgewickelten Ansicht in unterschiedlichen Ausführungen.

An embodiment of the invention is shown purely schematically in the drawings and will be described in more detail below. Show it:

Fig. 1:

a tumble dryer in a sketched sectional view;

Fig. 2:

the drum in a perspective view and

3 to 7:

the drum shell in a developed view in different versions.

In Fig. 1 is a purely schematic representation of a dryer 1, shown with a housing 2 and a drum 3 arranged therein. The position and direction data relate to the operating position of the dryer 1. The drum 3 is rotatably mounted, so that in the drying process, the laundry items 8 are swirled around while the air or heated air 12 flows through the drum 3. The housing 2 has a loading opening 5, via which the interior of the drum 3 can be reached. The loading opening 5 can be closed by means of a door 4. The air flow 12 is generated by means of a blower 5 and blown through the process air duct 7 into the drum 3. With a heater 6 in the process air duct 7, the air 12 is heated. In the case of a condenser dryer, a condensation device 11 is furthermore provided, which extracts the moisture from the process air 12 and supplies the condensation liquid to a collecting container 9. With a motor 10, the fan 5 and the drum 3 is driven in rotation.

In Fig. 2 the drum 3 is shown, which consists of a jacket 19 and two opposite end walls 20, wherein here for better illustration of the inside of the jacket 19, the front end face is removed. On the inner side 19 a of the jacket 19 are distributed over the circumference a plurality of driver ribs 21, in this example, three, attached. The driver ribs 21 are formed in profile approximately V-shaped. The drum shell 19 is here divided into three sections, which are divided by the driver ribs 21. In this case, in each section, a structure of the segments 22 is formed such that a curved pattern, in this example an S-shaped pattern, forms on the jacket 19. The pattern is in this case designed such that on the drum shell 19 a curved or S-shaped smooth web 24 extends in the circumferential direction U or which extends within the portion between the driving ribs 21. The web 24 is not provided here with bulges or with curved segments 22. The web 24 is embedded laterally by the segments 22, so that it does not hit one of the front edges 19b 19c. To form the arch structure on the drum shell 19, the segments 22 are angular, in this example 6-square executed with their contours 22a (FIG. Fig. 4a ) lie against each other and form a honeycomb arrangement.

In Fig. 3 the jacket 19 is shown as a settlement. The jacket 19 is divided in the circumferential direction U into a plurality, in this example three, sections 26, which are provided with the structure of arched, polygonal, here hexagonal segments 22. Here it can be seen that the segments 22 are formed differently in size with respect to their surface, such that a curved, here an S-shaped pattern of the structure results on the surface of the jacket 19. In the middle region, a curved or S-shaped web 24 is formed, due to its S-shape, the circumferential center line, here Equatorialline EQ called, crossed or oriented to it. In the jacket 19 no holes for the air are provided here.

In Fig. 4a is a single section 26 of the shell 19 ( Fig. 2 ) in detail. It can be seen here that all the segments 22 have approximately the same length L, wherein they differ with regard to their width B, such that a curved, here an S-shaped pattern of the structure results, wherein additionally an S-shaped web 24 is formed without segments 22 and without bulges. In Fig. 4b the jacket 19 is shown in the sectional plane AA. It can be seen here that the segments 22 have a curvature 23 towards the interior of the drum or are arched, wherein they are arranged with their edge contours 22a at a distance R from the respectively adjacent segment 22. It can be seen here that the bulges 23 have approximately the same height h, the height h being approximately 0.1 to 2 mm. It is alternatively possible to vary the height h depending on the size, ie of the length L and / or width B of the segments 22. It can also be seen here that the web 24 has no curvature. The web 24 in this case has a width B of about a segment 22, as it undistorted or as it represents in its length L.

In Fig. 5a an embodiment of the drum 3 is outlined, in which the jacket 19 is provided with a wider S-shaped web 24, as in the example according to FIG Fig. 4a the case is. The web 22 is designed differently wide in its course in the circumferential direction U, wherein the width B of the web 24 at the narrowest point in the center region of the drum portion 26 or the drum circumference approximately the length L of a segment 22 and at the widest point in the apex area or at the ends of the S-shaped web 24 approximately the length L of 1.5 to 2 times a segment 22 corresponds. The web 22 is provided with additional curved surfaces 27 facing the drum, the curved surfaces 27 each having a circumferential length U of the jacket 19 of about 0.4 to 0.8 times the length L of a nearest segment 22 and a width B of about 0.4 to 0.8 times the width B of a nearest segment 22. In the sectional view Fig. 5b are the curved to the drum outer segments 22, the smooth area of the web 24 and the curved segments 27 can be seen in the web 24. The smaller segments 27 arranged on the web 24 may also be arched towards the interior of the drum in order to increase the entrainment effect on the items of laundry 8 (FIG. Fig. 1 ) to reinforce. Furthermore, a combination of outward bulges and inward bulges is possible.

Fig. 6 shows an embodiment of the drum shell 19 in an unwound representation, in which the segments 22 are formed so differently that results in a curved or S-shaped structure 28 which extends along the entire shell circumference. There is no buckle-free web 24 is formed so that only the distortion of the segments forms the curved or S-shaped pattern.

Fig. 7 shows an embodiment with a buckle-free web 24 in the middle third of the shell 19. The S-shape is designed so that a single S or a single swing back and forth over the entire shell circumference extends. The already mentioned embodiments according to Fig. 5a and 5b with differently wide web 24 and / or with additional curved surfaces 27 (FIG. Fig. 5 ) in the web 24 can also be carried out so that a single S extends over the entire circumference of the shell.

Claims (14)

Drum (3) for a tumble dryer (1) in which the drum (3) can be rotatably supported by a horizontal or inclined axis (7) comprising an approximately cylindrical or frusto-conical jacket (19) having on its surface a structure, which consists of individual curved segments (22) comprises,
characterized,
that the size of the segments (22) is formed differently, such that the structure of the arcuate segments (22) on the surface of the shell (19) forms a curved pattern. Drum according to claim 1,
characterized,
that the segments (22) are curved to the outside toward the drum. Drum according to claim 1,
characterized,
that the pattern is at least simply S-shaped curved. Drum according to claim 3,
characterized,
that the segments (22) in the circumferential direction (U) of the shell (19) each have at least approximately the same length (L) and in the transverse direction each have a different width (B) have, such that the S-shaped (curved pattern in the circumferential direction U) of the jacket (19) is formed. Drum according to claim 1 or 3,
characterized,
that the segments (22) in the circumferential direction (U) of the shell (19) each have a different length (L), so that the curved or S-shaped pattern corresponding transverse to the circumferential direction (U) of the jacket (19) is formed. Drum according to claim 3,
characterized,
that in the circumferential direction (U) extending S-shaped pattern (28), starting from the approximate circumferential (U) circumferential center line (EQ) of the jacket (19), a first vertex toward the first jacket edge (19 a) and a second vertex toward the opposite second jacket edge (19b). A drum according to any one of claims 1 to 6,
characterized,
in that the drum casing (19) is divided into at least two sections (26) and in each section (26) an S-shaped pattern of arched segments (22) is arranged in each case. Drum according to claim 1,
characterized,
in that the curved segments (22) are formed by polygons which adjoin one another with their edge contours directly or at a distance (R), the segments having a length (L) and a width (B) of approximately 1 to 5 cm. Drum according to claim 1 or 2,
characterized,
that the bulges (23) have approximately the same height (h) and that the height (h) is approximately 0.1 to 2 mm. Drum according to claim 1 or 2,
characterized,
that the domes (23) each have a height (h) which is approximately proportional to the length (L) and width (B) of the segments (22), wherein the height of about 1/500 to 1/20 of the width (B ) or the length (L) of the respective segment (22). Drum according to one of claims 1 to 10,
characterized,
in that the curved or S-shaped pattern is formed on the jacket (19) in such a way that a curved or S-shaped web (24) without bulges or bulge structure results. Drum according to claim 11,
characterized,
that the web (24) approximately the width (B) which corresponds to the length (L) of a segment (22) in the circumferential direction (U). Drum according to claim 11,
characterized,
that the width of the web (24) varies, wherein the width (B) of the web (24) at the narrowest point in the central region of the drum portion (26) or the drum circumference (U) is approximately the length of a segment (22) and widest Point in the apex area or at the ends of the S-shaped web (24) is approximately equal to the length of 1.5 to 2 times a segment (22). Drum according to one of claims 11 to 13,
characterized,
in that the web (24) is provided with additional curved surfaces (27) directed towards the outside and / or inside of the drum, the curved surfaces (27) each having a circumferential length (U) of the jacket (19) of approximately 0.4 to 0.8 times the length (L) of a proximal segment (22) and having a width (B) of about 0.4 to 0.8 times the width (B) of a proximal segment (22).

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