EP1118704A1 - Drum washing machine - Google Patents

Abstract

A washing machine or dryer has a drum, which is located in a washing container in a horizontal or inclined position. The drum casing is made, at least in part, of sheet metal and equipped with a dome structure directed in a direction of the drum interior. The perforations (16) in the drum casing are located on the outer edges (17.1) of a dome - the edges are directed at the drum exterior. Alternatively, the perforations (16) are located in drum sections without a domed structure.

Description

The invention relates to a washing machine or a washer-dryer with an in a tub horizontal or inclined and rotatable drum with a jacket and two cover surfaces, the jacket or one of the cover surfaces with a removal opening is equipped, and wherein the jacket is wholly or partly made of sheet metal, which is provided with a domed structure facing the inside of the drum.

Drums of washing machines or washer dryers usually consist of sheet metal structures. Because of the high spin speeds of up to 1600 rpm, the drum construction great demands are placed on strength, shape retention and rigidity. It is known from DE 44 37 986 A1 and from DE-OS 25 57 215, the sheet metal which the drum is manufactured to provide with arched structures to increase its strength.

In washing machines, it is still common for the drum jacket and possibly also the top surfaces to be provided with holes so that an exchange of lye between the laundry and the tub is possible is guaranteed. These holes have diameters in today's washing machines in the order of 3.5 mm. Thereby in the manufacturing process the drum First punch holes with a diameter of approx. 2.5 mm in a sheet metal coil and then through a stamping process, the so-called penetration, deepened in a funnel shape and widened to 3.5 mm. When molding and welding a cut coil part The recess of the holes is directed outwards in a cylindrical jacket. this happens for the purpose that any burrs on the edge of the hole do not protrude into the inside of the drum and so the contact of the laundry to these ridges is avoided. The putting through and The associated structuring of the inside of the drum gives the effect that on the one hand the proportion of the flat surface on the entire lateral surface is reduced and on the other hand the light entering the drum is reflected diffusely. On the one hand, this creates the impression of solidity and shine, i.e. high-quality material conveyed, and scratches also fall or less contamination.

A washing machine is known from US Pat. No. 2,591,143, the drum of which has a curvature in Form of a corrugation extending over the entire length of the drum shell is. The perforated drum is arranged in the outwardly directed recesses. This leads to residual water in the flat areas between the holes stops and drainage deteriorates. In addition, such a drum structure the laundry is rubbed very badly and thereby damaged.

In the case of the aforementioned drums, it has proven disadvantageous that the relatively large ones Holes in textiles for pimples, laundry damage and the passage of threads and Lead foreign bodies. It has therefore already been proposed to increase the hole diameter reduce (DE-OS 14 10 985) and / or limit the perforation to parts of the jacket (DE 28 26 506 A1).

If you want to get through holes with a diameter of 2 mm, you can Punching tools have a maximum thickness of approximately 1.2 mm. This would be the case for Washing machine drums quickly used sheet thicknesses to break off the tools to lead. For this reason, it is not possible in an automated manufacturing process To produce washing machine drums with through holes of 2 mm in diameter.

Drums with hole diameters around 2 mm, which do not have to be put through, therefore have a relatively smooth surface, which has the optical properties described above absence. The same applies to drums with perforations in some areas, because here the unperforated jacket areas are completely smooth. It is also the case with such drums disadvantageous that residual water remains on the smooth surface and the drainage deteriorated.

The invention therefore presents the problem of designing the drum of a washing machine in such a way that that at the same time good optical properties and complete emptying of the Residual water can be reached.

According to the invention, this problem is solved by a drum washing machine with the features of independent claim 1 solved. Advantageous refinements and developments the invention result from the following dependent claims.

The advantages achievable with the invention exist in addition to the solution of the aforementioned Problem in increasing the stability of the drum. This can reduce the cost of Use of thick sheets or complex forming processes (e.g. expanding) are reduced become. Alternatively, the safety distance can be maintained while maintaining the sheet thickness between the drum and the tub, which, when spinning, touches the drum and Should prevent the tub from being reduced. This reduces the so-called Dead volume between drum and suds jacket, d. H. the free fleet is reduced (lower water and energy consumption) and the drum volume can be increased. Through the formation of the arch structure as polygons directed towards the inside of the drum and the The arrangement of the holes in sections without a curved structure is the perforation easier to implement because it does not have to be adapted to the arch structure. The holes can in the border areas adjacent to the cover surfaces (cap, bottom) or in the Middle region of the jacket can be arranged.

It is also advantageous if the holes are compared to those of conventional drum washing machines are reduced in number and / or in diameter. This is the passage reduced by fluff or threads, which is more gentle on the laundry.

Figur 1

den allgemeinen Aufbau einer Trommelwaschmaschine

Figur 2

den Längsschnitt durch eine Trommel (3)

Figur 3

schematisch die Gestaltung der Wölbstruktur und der Lochung in einem Bereich des Trommelmantels (3.1)

Exemplary embodiments of the invention are shown purely schematically in the drawings and are described in more detail below. It shows

Figure 1

the general structure of a drum washing machine

Figure 2

the longitudinal section through a drum (3)

Figure 3

schematic of the design of the arch structure and the perforation in an area of the drum casing (3.1)

The drum washing machine (1) designed according to the invention has a tub (2) in which a drum (3) for receiving laundry (4) is rotatably mounted. The drive the drum (3) is driven by a motor (13) via a V-belt (13.1). The tub (2) is swingably suspended on springs (5) in the housing (6) and becomes Damping of these vibrations in the lower area by shock absorbers (7) compared to Supported base (8).

The detergent / fabric softener required to carry out a washing program will be the Suds container (2) via a detergent dispenser (9) with connected connecting hose (10) fed. For this purpose, the desired substances can be added by the user Corresponding compartments (11) of a detergent drawer (12) can be filled. About an in the water supply, not shown, the entire subject at the beginning of of the respective program part washed into the tub (2).

A microprocessor control (MC) is used to control the different washing programs provided that via signal lines (14) with various sensors and the controls connected is. It issues time and status-dependent commands via control lines (15) to various actuators (motors, valves, display elements ...).

The drum (3) is in an automatic manufacturing process described in more detail elsewhere (not shown). This is done first for the drum jacket (3.1) cut a metal strip from a coil and punch it with the desired one Provide perforation (16). The sheet metal strip is then bent in a circle and welded the two mutually facing edges. The resulting cylinder is provided with shaping and stabilizing contours by known expansion processes. Then a vaulted structure is created by a method known from DE-OS 25 57 215 put on the coat. Then the floor (3.2) and the Cap (3.3).

Figure 3 shows a section of the drum shell (3.1) with the basic structure of the Arch structure and the arrangement of the holes (16) according to the invention:

The jacket (3.1) is preferably in sections with inwardly curved polygons Hexagons (17).

The arrangement of the holes (16) is determined by the requirement for rapid, residue-free Water drainage and good degree of textile drainage when spinning with pumps or only pumping, optimal laundry protection, low foreign body sensitivity and good looks.

Rows of holes are on the front and rear edges (3.5) of the drum shell (3.1) are not arched. Additionally or alternatively, there are more limited, unstructured ones Zones (3.6) with holes (16) possible, for example as shown in Figure 3, in the middle of the drum casing (3.1). The domed areas can be completely be unperforated so that the structure only serves to secure the drum (3), but it can also the perforation (16) described above in the preferred locations within the Vaulted structure, e.g. B. the corner points (20) of the polygons (17).

The diameter of the drum (3) can be the same with a suitable material thickness Tub diameter can be increased by up to 10 mm, if not one Prevents water jacket formation when spinning. This allows the smallest distance between the drum casing (3.1) and the tub container is only approx. 5 mm.

Drum jackets (3.1) can be provided with the arch structure as cylinders and before or afterwards subjected to a further forming process (e.g. expansion). Just like that it is possible to produce finished circuit boards or coil material with curved structures (see DE 44 37 986 A1) to process or circuit boards or coil material in a continuous To provide the manufacturing process with the arch structures, to punch before or after and undergo further forming processes (e.g. roll forming, embossing, pressing, etc.), as well as to shape a cylinder.

The considerations can also be applied analogously to the bottom and the cap.

Claims (5)

Washing machine or washer dryer with a drum (3) mounted horizontally or inclined and rotatable in a tub (2) with a jacket (3.1) and two cover surfaces (3.2, 3.3), the jacket (3.1) or one of the cover surfaces (3.2, 3.3 ) is equipped with a removal opening, and the jacket is at least partially made of a sheet metal which is at least partially provided with a domed structure directed towards the inside of the drum,
characterized, that the arch structure consists of polygons (16) directed towards the inside of the drum and that the holes (16) are arranged in sections (3.5; 3.6) of the jacket (3.1) which are designed without a domed structure. Drum washing machine (1) according to claim 1,
characterized,
that the holes (16) are arranged in at least one non-arched section (3.5) of the jacket (3.1) adjoining the cover surface. Drum washing machine (1) claim 2,
characterized,
that the holes (16) are arranged in a non-arched central region (3.6) of the casing (3.1). Drum washing machine according to at least one of claims 1 to 3,
characterized,
that the holes (16) are smaller than those of conventional drum washing machines (1) in diameter (d) and have a diameter (d) of approximately 2 mm. Drum washing machine (1) according to claim 4,
characterized,
that the smallest distance between the drum casing (3.1) and the tub casing is approx. 5 mm.

Images