EP2446797B1 - Dishwasher with at least one pre-assembled bitumen pad for muffling and/or soundproofing a wall section - Google Patents

Description

The present invention relates to a dishwasher, in particular a domestic dishwasher, with at least one wall part for limiting a washing chamber, which is provided with at least one, in particular prefabricated, bitumen mat for Entdröhnung and / or sound insulation of the wall part.

Domestic dishwashers have a washing chamber, which is for receiving dishes, especially dishes, during a wash cycle, also called rinsing process, is provided. The rinsing chamber is usually limited by several wall parts. The use of prefabricated bitumen mats for Entdröhnung of such wall parts is known. However, bitumen mats have a high heat storage capacity, so that the temperature balance of the dishwasher during the execution of a rinse cycle can be adversely affected.

The publication DE 198 58 002 A1 discloses a noise and heat insulation of bitumen material, in particular for washing containers made of metal of dishwashers, which at least partially covers its sheet material for noise and heat insulation with bitumen mats or the like. The bitumen material is provided with a thermal insulating layer in the boundary layer to the sheet material. To achieve improved thermal insulation. the use of bitumen material, the material may be provided in the boundary layer to the sheet material of the washing container with a mechanically stable, thermal insulating layer consisting of expanded glass granulate or expanded clay. The boundary layer may additionally be provided on the container side with a contact adhesive, which produces the detachable connection between the insulation and the sheet material of the washing container. The adhesive bond may be a hot melt adhesive or a peelable pressure sensitive adhesive.

The object of the present invention is to provide a dishwasher, in particular a domestic dishwasher, in which the temperature balance is improved.

The object is achieved in a dishwasher of the type mentioned above in that the bitumen mat is bonded by means of at least one, in particular only exactly one, thermally insulating adhesive layer on the wall part, which has a lower thermal conductivity than the bitumen mat. The adhesive layer has micropores and the proportion of micropores in the volume of the adhesive layer is at least 80%, preferably at least 90%, particularly preferably at least 95%.

Micropores are in particular closed cavities whose dimensions are typically in the range of one micron. By micropores, the thermal conductivity of the material of the adhesive layer against a full-volume adhesive layer of the same material can be greatly reduced, which can lead to a particularly strong energy savings. In particular, the heat conductivity of a hot melt adhesive or a reactive hardened bituminous mixture can thus be adjusted in accordance with the invention.

A strong reduction of the thermal conductivity and consequently of the energy requirement results from the stated proportions of the micropores in the volume of the adhesive layer.

The rinsing chamber of the dishwasher according to the invention can be arranged in a box-shaped washing container, which is composed of several wall parts. For example, the rinsing container may comprise a first wall part which is designed as a rinsing container hood and forms a first side wall, a second side wall and a cover of the rinsing container, so that the rinsing chamber is bounded on two opposite sides and upwards. A second wall part of the washing container may be formed as a rear wall and limit the washing chamber to a third side. Furthermore, the rinsing container may comprise a third wall part, which is called a floor pan, also called a rinsing pan, and which limits the rinsing chamber downwards. The remaining side of the washing can be closed by a movable door, which has a trained as an inner door fourth wall part, which with the door closed Flushing chamber limited to the fourth side. But there are also other arrangements of wall parts conceivable. For example, the door could be provided at the top of the rinsing chamber, so that the rinsing chamber can be loaded from above.

The rinsing chamber limiting wall parts of the washing and / or the door are usually made thin-walled. Thus, depending on the material, wall thicknesses are common, for example in the range of 0.3 to 2 mm. During the execution of a rinse cycle, the wall parts are subjected on their inside to circulated rinsing water, in particular spray jets, so that they are particularly strongly excited to vibrations, which may cause unwanted noise. By now at least one bitumen mat is applied to one or more of the wall parts, the noise emission of the dishwasher can be substantially reduced.

A bituminous mat is understood in particular as meaning a mat which is produced using a binder of bitumen, also called earth pitch, for example petroleum distillate bitumen, and / or of bituminous binders, such as natural asphalts, polymer bitumens, tars, pitches, paraffins, natural or synthetic resins and / or or distillation residues of fats and oils.

The term "prefabricated" means, in particular, that the bitumen mat is first produced independently of the wall part for which it is intended as a semifinished product or precursor having defined dimensions, thickness and / or geometric shape, in order then to be able to fasten it to the wall part. For example, a prefabricated bitumen mat can be made by cutting or punching a piece of the desired size from a base mat.

The term "deadening" refers to the reduction or avoidance of noise caused by excitation of the component or parts thereof to vibrations. Disturbing noises can arise in particular on thin-walled components, such as, for example, the Spülbehälterwandungen and / or the door of a dishwasher, which are acted upon by rinse water and thereby excited to vibrate. But it is also possible that such vibrations be generated by actuators, such as pumps, blowers or the like. The Entdröhnung is now achieved in particular by means of the bitumen mat an additional mass is applied to the typically thin-walled component, so that the frequencies of the vibrations occurring are smaller, so that the resulting noise is less disturbing. In addition, internal friction in the bitumen mat may optionally convert at least part of the vibration energy into heat, so that the intensity of the generated noise decreases. This can be accompanied by a sound absorption in an advantageous manner.

Furthermore, the respective bitumen mat additionally or independently of a Entdröhnung in particular also for a "sound insulation", that is to provide sound reflection. In particular, for example, sound from the interior of the rinsing chamber of the rinsing container of the dishwasher can be thrown back into the rinsing chamber interior by the component, preferably the wall part of the rinsing container, which is bonded to one or more bitumen mats by means of the thermally insulating adhesive layer. In an analogous manner, of course, the sound reflection for the remaining components such as for the receiving chamber or the cavity in the base support below the washing, where the circulating pump is arranged to work.

A typical rinse cycle of a dishwasher according to the invention comprises in this time sequence a pre-wash cycle, a cleaning cycle, an intermediate rinse cycle, a rinse cycle and a drying cycle.

After the operator has started a corresponding wash program, the pre-wash cycle is started, wherein fresh water is first introduced into the dishwasher by a corresponding activation of the fresh water holding device. By appropriate control of the circulation pump, the fresh water is then circulated as rinse water, so as to rid the dishes of coarse dirt. After a predetermined time then at least a portion of the now contaminated rinse water is pumped out under appropriate control of the drain pump and the pre-wash cycle ends.

At the beginning of the subsequent cleaning cycle, further fresh water is introduced into the washing container while the fresh water receiving device is again activated brought in. This is usually heated by driving the heater in a heating phase of the cleaning cycle. During the heating phase of the cleaning cycle, cleaning agent, which is now located in the washing container, is as a rule added to cleaning agent via a detergent metering device controlled by the sequence controller. Furthermore, during the heating phase of the cleaning cycle, the circulation pump is controlled so that the rinse water is circulated so as to be able to remove stubborn dirt from the items to be washed. When the temperature of the wash cycle reaches a predetermined value by the wash program, for example 50 ° C., this is detected by means of a sensor for the temperature of the wash cycle, whereupon the process control device switches off the heating device. Subsequent to the now completed heating phase of the cleaning cycle, a subsequent cleaning phase of the cleaning cycle is carried out with a predetermined period of time during which the rinsing water is circulated further. At the end of this Nachwaschphase the drain pump is controlled again, so that at least a portion of the rinse water of the cleaning cycle is pumped out.

At the beginning of the subsequent intermediate rinse cycle, the rinse water is replenished in the rinse tank via the fresh water intake device. Usually, the rinse water of the intermediate rinse cycle is not heated, but circulated by means of the circulation pump. By means of the intermediate rinse, in particular, detergent residues can be removed from the items to be washed. After a predetermined period of time, the rinse water of the intermediate rinse cycle, which now comprises detergent residues, is at least partially pumped out.

At the beginning of the subsequent rinse cycle, the fresh water receiving device is controlled again to bring fresh water into the washing. This is mixed with rinse aid by a rinse aid addition device, heated by activation of the heating device and circulated by appropriate activation of the circulation pump. Upon reaching a designated temperature, the circulation pump and the heater are turned off. Furthermore, the rinse water is pumped out via the drain pump and the rinse cycle finished. The rinse cycle is used in particular to avoid staining on the cleaned items to be washed, which is achieved essentially by the chemical properties of the rinse aid. Furthermore, the rinse cycle generally serves to wash items for the now following Prepare drying cycle by this is brought to a relatively high temperature, for example, 70 ° C.

During the subsequent drying cycle, in which no new rinse water is introduced into the washing, evaporated due to the high temperature of the dishes, the still adhering rinse water. This condenses then especially on the walls of the washing and collects in a lower portion of the washing. From there, the rinse water is pumped out after a predetermined time by means of the drain pump and the drying cycle is completed.

The illustrated basic sequence of a typical rinse cycle can be modified in many ways. For example, different time constants or different temperatures can be specified. It is also possible to omit individual partial rinses, such as, for example, the pre-rinse cycle or the intermediate rinse cycle, or to carry out individual partial rinses, for example the cleaning cycle, several times in succession. In this way it is possible to adapt the intended course of the wash cycle to different applications. It is also possible to carry out the pre-wash cycle and / or the intermediate wash cycle while heating the rinse water.

By now the respective bitumen mat is glued by means of at least one, in particular exactly one, thermally insulating adhesive layer on the wall part, which has a lower thermal conductivity than the bitumen mat, the energy requirement for heating the rinse water can be significantly reduced. This applies in particular to the heating of the rinse water used in the cleaning cycle or in the rinse cycle. The energy-saving effect is ultimately achieved by heat transfer from the washing container to the bitumen mat can be reduced by the thermally insulating adhesive layer during the execution of a rinse, so that the rinse water heats up faster and thus reaches the respective intended temperature faster. It preferably exerts at least one heat-transfer-reducing or braking blocking effect or a thermally decoupling function between the respective wall part and the bitumen mat to be applied to it and to be applied in each case.

The thermal conductivity characterizes the ability of a material to transfer heat within it. It is usually denoted by the symbol λ and is expressed in watts per meter times Kelvin (W / mK).

The thermally insulating adhesive layer also serves to attach the bitumen mat to the wall part and thus has a dual function. Compared to solutions in which an insulating layer of a prefabricated foam adhered by means of a first conventional adhesive layer on the wall part and a prefabricated bitumen mat with a second conventional adhesive layer is adhered to the foam, two layers can be saved, which simplifies the production of the dishwasher, without disadvantages in terms of energy savings would be to get.

In addition, the reduction in the number of layers leads to a closer vibration coupling between the wall part and the bitumen mat. In other words, this prevents the wall part from swinging more than the bitumen mat. In this way, the noise behavior of the dishwasher can be improved.

It goes without saying that a plurality of bitumen mats can also be adhesively bonded to the wall part, in particular side by side and / or one above the other, by means of at least one, in particular only exactly one, thermally insulating adhesive layer.

According to an advantageous development of the invention, the thermal conductivity of the adhesive layer is at most 60%, preferably at most 40%, particularly preferably at most 20%, of the thermal conductivity of the wall part. In this way, the heat conduction from the wall part to the bitumen mat can be significantly reduced even with a relatively thin adhesive layer running and thus a significant energy saving can be achieved.

According to an advantageous development of the invention, the thermal conductivity of the adhesive layer is at most 0.12 W / mK, preferably at most 0.08 W / mK, particularly preferably at most 0.04 W / mK. These values, which are at a temperature of 20 ° C are well below the thermal conductivity of common bitumen mats, which for example have a thermal conductivity of 20 W / mK, so that a significant energy saving can be achieved.

According to an advantageous development of the invention, the adhesive layer has a modulus of elasticity of at least 20 N / mm ² , preferably of at least 100 N / mm ² , particularly preferably of at least 500 N / mm ² . The modulus of elasticity is the ratio of a surface-related force to the change in length of a material caused thereby. The elastic modulus is usually denoted by the symbol E and is expressed in Newtons per square millimeter (N / mm ² ). The values given may refer to values determined at normal pressure and at 20 ° C. The intended high values of the modulus of elasticity of the adhesive layer prevent the wall part from being vibrationally decoupled from the bitumen mat. In this way, a particularly good Entdröhnung and / or sound insulation of the wall part can be achieved.

After an expedient development of the invention, the adhesive layer consists of a hot melt adhesive. Hot melt adhesives are also adhesives which are liquefied by heating and applied in a liquid state in order to produce a compound on cooling and on solidification. Hotmelt adhesives result in a permanently stable connection between the wall part and the bitumen mat, whereby a strong oscillation coupling can also be achieved. In particular, hot melt adhesives may be based on polymers such as, for example, polyamides (PA), polyethylenes (PE), amorphous polyalphaolefins (APAO), ethylene-vinyl acetate copolymers (EVAC), polyester elastomers (TPE-E), polyurethane elastomers (TPE-U). , Copolyamide elastomers (TPE-A) and so forth. In particular, a PU (polyurethane) foam layer can be selected as the thermally insulating adhesive layer.

According to a particularly advantageous embodiment of the invention, the adhesive layer consists of a reactive cured from a bituminous mixture. Reactively curable bituminous mixtures expediently include at least one base binder of bitumen, also called Erdpech, or bitumen-like Binders, which has such a high viscosity at a given processing temperature that it behaves almost like a solid.

The base binder may be, for example, petroleum distillate bitumens, natural asphalts, polymer bitumens, tars, pitches, paraffins, natural or synthetic resins and / or distillation residues of fats and oils.

In order to be able to form the bituminous mixture into an adhesive layer, it expediently contains at least one fluxing agent which lowers the viscosity of the mixture to such an extent that it can flow at the intended processing temperature, ie behaves like a liquid. Fluxing agents are preferably low-volatility solvents, in particular low-volatile oils based on mineral oils, tar oils, vegetable and animal fats and oils, carboxylic acids, and nonvolatile technical plasticizers of synthetic polymers, which remain after curing of the bituminous mixture in the bituminous mixture, so do not evaporate. Also, fluxing agents based on vegetable or mineral oils and / or resins may be appropriate.

In order to cause the bituminous mixture to harden after the adhesive layer has been formed, at least one reactive additive is added to the mixture prior to the formation of the adhesive layer to produce a physical and / or chemical effect which increases the viscosity of the mixture. In this case, the effect of the reactive additive can be initiated automatically by the reactive additive or by the additional addition of at least one activator.

The reactive additive may, if appropriate in cooperation with the activator, in particular preferably irreversibly cancel the effect of the fluxing agent, for example by crosslinking, precipitation or by binding to the base binder.

The reactive additive may comprise, for example, chelating agents, acid anhydrides, alcohols, carboxylic acids, fatty amines, inorganic salts, cements, lime, gypsum, dolomite, ashes, slags, glasses, silica gels and / or alums.

The activator may include water, glycols, fatty alcohols, surfactants, acids and alkalis, metal salts, sulfur, peroxides, latex and / or synthetic resins.

The bituminous mixture may also contain other additives, fillers and so on.

Also fluxing agents based on vegetable and / or mineral oils and / or resins may be appropriate. However, in general, the fluxing agents can also be obtained from renewable, ie regenerative raw materials. Additionally or independently thereof, the base binder, the reactive additive and / or the activator may be made from at least one renewable raw material.

The adhesive layer of the reactively cured bituminous mixture has superior adhesive properties both on the bitumen mat and on the usual surface materials of the wall parts of dishwashers compared to known adhesives for attaching bitumen mats to wall parts of dishwashers. In particular, the adhesive layer adheres to plastic parts, especially on parts that are made of polypropylene, particularly good. But even on parts made of bare metal, in particular made of bare stainless steel, a sufficient and reliable adhesion or cohesive, that is material-material connection is ensured. The adhesion to metallic wall parts of the washing container and / or the inner door can be optionally further increased by a primer, paint or a plastic coating.

Due to the good adhesive properties of the adhesive layer of the reactively cured bituminous mixture can be dispensed with in most cases on a pretreatment of the surface of the wall part, such as roughening, grinding, Plasmatieren, flaming and the like, which simplifies the production of the dishwasher. A primer or other pretreatment of the component to be coated with the bitumen mat is often not necessary in order to achieve a sufficiently reliable adhesion of the adhesive layer to the component.

Compared to known hot-melt adhesives, which typically require a processing temperature of, for example, 130 ° C to 200 ° C, the adhesive layer can be prepared from the reactively cured bituminous mixture with appropriate selection of the components without applying heat at room temperature become. In this way, a significant energy saving can be achieved in the manufacture of the dishwasher. However, it may be useful to provide in the manufacture of the adhesive layer, a supply of heat to accelerate the curing. However, significantly lower temperatures, for example 60 to 70 ° C., are generally sufficient for this, for example, in the case of a heat-adhesive bond.

In addition, the hardening of the reactive bitumen itself does not lead to an inadmissibly strong exothermic heat development. Also, the introduction of an inadmissibly high heat energy is avoided by an external heat source for the curing process.

Thus, by using the adhesive layer of the reactively cured bituminous mixture when attaching the bitumen mat to the wall part, the thermal load of the walled part to be deadened and / or sound-deadened, the prefabricated bitumen mat and / or further components of the dishwasher can be kept low or completely avoided. As a result, in many cases less temperature-stable components can be used than hitherto, which can reduce the manufacturing costs of the dishwasher.

In particular, it is now possible to properly apply a bitumen mat to a heat-sensitive plastic component, such as a Spülbehälterwandung - such as the bottom tray - made of plastic, preferably polypropylene (PP) without the plastic component in an inadmissible manner thermally stressed, deformed or is even damaged.

Compared with the use of known cold adhesives, which typically contain a volatile and curing solvent, the use of the adhesive layer of the reactively cured bituminous mixture may be more environmentally friendly.

The adhesive layer of the reactive cured bituminous mixture is also extremely durable and can thus outlast the useful life of a dishwasher in most cases.

At least part of the micropores may be made by foaming a base material of the adhesive layer, for example by means of a foaming additive. Likewise, at least a portion of the micropores may be made by introducing porous solids into the adhesive layer. Suitable for this purpose are, in particular, aerogels which are highly porous.

According to an advantageous embodiment of the invention, the adhesive layer is laterally bounded by at least one projecting on the wall part limiting element. In this way, it can be prevented that the respective thermally insulating adhesive flows away from the surface of the wall part before the complete curing or even drops from it. In addition, the contact surface of the wall part can be increased with the adhesive layer, so that the connection of the wall part and adhesive layer is more resilient. It can be provided that the adhesive layer is partially bounded by the at least one projecting boundary element or completely bordered. The limiting element may in particular be formed as a web whose height may exceed the height of the adhesive layer, whereby the bitumen mat may be protected at its edge against external influences, for example in the manufacture of the dishwasher.

According to an expedient development of the invention, the respective bitumen mat is glued to a three-dimensionally structured surface of the wall part. In this way, the contact surface of the wall part with the adhesive layer can be further increased, so that the connection of the wall part and adhesive layer is even more resilient. The structured surface may have an embossing, for example in the form of honeycombs, which is easy to produce, in particular, when the wall part is preferably a plastic component or optionally also a sheet metal component.

According to an advantageous development of the invention, the structured surface has at least one web and / or at least one groove, or some other increase and / or depression. These effect a three-dimensionally structured surface and can in particular be formed in a simple manner on cast parts, in particular plastic injection molding. So it is expediently mechanical aids, such as depressions and / or elevations on the surface to be provided with the adhesive of the component to be coated with the bitumen mat intended. These may be in particular ribs, projections, webs, beads, grooves, grooves, undercuts, and so on. The surface to be coated with the adhesive to be coated with the bitumen mat thus expediently has, in general terms, a three-dimensionally structured surface.

According to an expedient development of the invention, the wall part is drowned out by a layer arrangement and / or sound-insulated, which is formed exclusively by the bitumen mat and the respective adhesive layer. In this way, an effective and permanent Entdröhnung and / or sound insulation of the wall part can be effected in a simple manner. In principle, however, it would be possible to arrange several adhesive layers and bitumen mats stacked or one above the other. Also, several bitumen mats can be glued to each other with and without distance from each other by means of the bituminous mixture to the respective entdröhnende and / or sound-insulating component.

According to an advantageous development of the invention, the bitumen mat has a maximum thickness in a range of 0.8 to 8 mm, preferably in a range of 1.2 to 6 mm, particularly preferably in a range of 1.6 to 4 mm. In the areas mentioned, it is possible to achieve adequate sound insulation and / or sound insulation of wall parts of the dishwasher with a low use of material. In this case, the bitumen mat can have a constant thickness or a variable thickness.

According to an advantageous embodiment of the invention, the adhesive layer has a maximum thickness in a range of 0.1 to 6 mm, preferably in a range of 0.2 to 3 mm, particularly preferably in a range of 0.4 to 1.5 mm, on. In the areas mentioned, the adhesive layer is sufficiently thick in order to achieve full surface contact of the adhesive layer with the wall part and / or with the bitumen mat even in the case of unwanted unevenness and / or intentional three-dimensional structuring of the surface of the wall part and / or the surface of the bitumen mat , This significantly reduces the heat flow from the wall part to the bitumen mat. In addition, a particularly stable arrangement is achieved with a particularly good Entdröhnwirkung. At the same time an excessive use of material is avoided.

The reproduced in the dependent claims and / or above advantageous embodiments of the invention may be provided individually or in any combination.

Fig. 1

ein vorteilhaftes Ausführungsbeispiel eines Spülbehälters mit einer ihm zugeordneten Tür für eine erfindungsgemäße Haushaltsgeschirrspülmaschine in einer schematischen räumlichen Ansicht und

Fig. 2

eine detailliertere Teildarstellung der Geschirrspülmaschine der Fig. 1, wobei ein Teil einer Bodenwanne des Spülbehälters und ein Teil einer mittels einer Klebeschicht aufgeklebten Bitumenmatte dargestellt ist.

The invention and its developments and advantages thereof are explained in more detail with reference to drawings. Each show schematically:

Fig. 1

an advantageous embodiment of a washing container with an associated door for a domestic dishwasher according to the invention in a schematic spatial view and

Fig. 2

a more detailed partial representation of the dishwasher of Fig. 1 , wherein a part of a bottom trough of the washing container and a part of a glued by means of an adhesive layer bitumen mat is shown.

In the following figures, corresponding parts are provided with the same reference numerals. In this case, only those components of a dishwasher are provided with reference numerals and explained, which are necessary for the understanding of the invention. It goes without saying that the dishwasher according to the invention can comprise further parts and assemblies.

The Fig. 1 shows a box-shaped washing container 1 of an embodiment of a dishwasher according to the invention. The rinsing container 1 comprises a first, U-shaped wall part 2, which forms a first side wall 3, a second side wall 4 and a cover 5 of the box-shaped rinsing container 1. Such a first wall part 2 is also referred to as a Spülbehälterhaube. A second wall part 6 of the washing container 1 is formed as a rear wall. Likewise, the washing compartment 1 as a third wall part 7 on a floor pan. The Spülbehälterhaube 2 and the rear wall 6 are each formed as a stamped and bent part made of stainless steel. In contrast, the bottom trough 7 is an injection-molded part made of plastic, in particular polypropylene.

In order to close an open side of the washing container 1, the washing container 1 is associated with a movable door 8, which has a fourth wall part 9 an inner door, which may also be a stamped and bent part made of stainless steel. The door 8 is in the Fig. 1 shown in an open position and can be transferred by pivoting in a closed position, so that a closed rinsing chamber 10 is formed in the items to be washed, such as dishes, can be cleaned by exposure to a rinse water. The rinsing chamber 10 is limited by the inner sides of the wall parts 2, 6, 7, 9, so that an uncontrolled discharge of rinse water is avoided. The arrangement of the wall parts 2, 6, 7, 9 is exemplary, with other arrangements of wall parts are conceivable. For example, a door could be provided on the upper side of the rinsing chamber 10, so that the rinsing chamber 10 can be loaded from above. Likewise, the rinsing chamber 10 could be arranged in a washing container, which is designed as a pull-out drawer.

The wall parts 2, 6, 7, 9 delimiting the washing compartment are supplied with circulating rinsing water, in particular spraying jets from the spray nozzles of spraying devices arranged in the interior of the washing compartment, such as rotating spray arms, during the execution of a washing cycle, so that they respectively can be excited to vibrations, which can cause unwanted noise. But it is also possible that such vibrations are generated by not shown actuators of the dishwasher, such as pumps, blowers or the like. Since the wall parts 2, 6, 7, 9 are made thin-walled, a particularly strong noise can result.

In order to prevent or at least reduce a disturbing noise development, sound deadening and / or soundproofing of the wall parts 2, 6, 7, 9 is provided by means of preferably prefabricated bitumen mats 11a to 11f.

The bitumen mats 11a to 11f are mats made using a binder of bitumen, also called earth pitch, or bitumen type binders such as polymer bitumen, tars, pitches and / or distillation residues of fats and oils. The term "prefabricated" means in particular that the respective bitumen mat 11a to 11f initially independent of the Wall part, for which it is provided, so here independent of the wall parts 2, 6, 7, 9, is manufactured as a semi-finished product with defined dimensions in order to then attach them to the respective wall part 2, 6, 7, 9 can. A prefabricated bitumen mat 11a to 11f can be produced, for example, by cutting out or punching out a piece of the desired size from a base mat which is preferably planar.

The Entdröhnung and / or sound insulation of the wall parts 2, 6, 7, 9 is now achieved in particular by means of the bitumen mats 11a to 11f each an additional mass on the typically thin-walled wall part 2, 6, 7, 9, is applied, so that the frequencies of the vibrations occurring are smaller, so that the resulting noise is less disturbing. In addition, by internal friction in the bitumen mats at least a portion of the vibration energy can be converted into heat, so that the intensity of the generated noise decreases. The bituminous mats 11a to 11f are expediently attached to surfaces of the wall parts 2, 6, 7, 9 facing away from the washing chamber, so that the bituminous mats 11a to 11f are not subjected to rinsing water.

In the exemplary embodiment, a first bitumen mat 11a is provided for deadening and / or soundproofing the floor pan 7. By way of example, the first bitumen mat 11a has a rectangular outline and a circular opening for an only indicated sump 12 of the dishwasher. A second rectangular bitumen mat 11 b is provided for Entdröhnung and / or sound insulation of the inner door 9 and a third rectangular bitumen mat 11 c for Entdröhnung and / or soundproofing of the rear wall 6. The Spülbehälterhaube 2 is by means of a fourth bitumen mat 11 d, which is arranged in the region of the first side wall 3, by means of a fifth bitumen mat 11e, which is arranged in the region of the second side wall 4, and by means of a sixth Bitumenmatte 11f, which in the area the ceiling 5 is arranged, entdröhnt and / or soundproofed. The respective bitumen mat is in each case glued seated over the entire surface of the Spülkammerinneren 10 of the washing compartment 1 outer surface of the respective Spülbehälterwandung and / or the inner door 9.

The Fig. 2 shows by way of example a more detailed partial representation of the dishwasher of Fig. 1 , wherein a part of a bottom trough 7 of the washing compartment 1 and a part of a by means of a thermally insulating adhesive layer 13 adhered bitumen mat 11 a is shown. The following explanations for the attachment of the bitumen mat 11a by means of the adhesive layer 13 on the bottom trough 7 apply mutatis mutandis to the attachment of the bitumen mats 11 b to 11f to the other entdröhnenden and / or entdröhnenden wall parts 2, 6, 9th

According to the invention, the bitumen mat 11a is glued by means of a thermally insulating adhesive layer 13 on the underside of the bottom trough 7, which has a lower thermal conductivity than the bitumen mat 11a. As a result, the energy required to heat the rinse water during the rinse cycle can be significantly reduced. The energy-saving effect is achieved in that by the thermally insulating adhesive layer 13 during the execution of a rinse a heat transfer from the rinsing chamber 10 to the bitumen mat 11 a can be reduced, so that the rinse water heated faster and thus reaches the respective intended temperature faster.

The thermally insulating adhesive layer 13 serves at the same time for fixing the bitumen mat 11a to the bottom pan 7 and thus has a dual function. Compared to solutions in which an insulating layer of a prefabricated foam adhered by means of a first conventional adhesive layer on the wall part and a prefabricated bitumen mat with a second conventional adhesive layer is adhered to the foam, two layers can be saved, which simplifies the production of the dishwasher, without disadvantages in terms of energy savings would be to get.

Furthermore, the adhesive layer 13 has micropores 16. Micropores 16 are in particular closed cavities whose dimensions are typically in the micrometer range. By micropores 16, the thermal conductivity of the material of the adhesive layer 13 can be stak reduced compared to a full-volume adhesive layer of the same material, which can lead to a particularly strong energy conservation.

The proportion of the micropores 16 in the volume of the adhesive layer 13 is at least 80%, preferably at least 90%, particularly preferably at least 95%. In this way results in a strong reduction of the thermal conductivity and consequently the energy demand.

In addition, the reduction in the number of layers results in a tighter oscillation coupling between the floor pan 7 and the bitumen mat 11a. In other words, in this way it is prevented that the floor pan 7 vibrates more than the bitumen mat 11a. In this way, the noise behavior of the dishwasher can be improved.

Preferably, the thermal conductivity of the adhesive layer 13 is at most 60%, preferably at most 40%, more preferably at most 20%, of the thermal conductivity of the bottom pan 7. In this way, the heat conduction from the bottom trough 7 to the bitumen mat 11a even with a relatively thin running adhesive layer 13 significantly reduced and thus a significant energy saving can be achieved.

The thermal conductivity of the adhesive layer 13 may be at most 0.12 W / mK, preferably at most 0.08 W / mK, particularly preferably at most 0.04 W / mK. These values, which are based on a temperature of 20 ° C, are well below the thermal conductivity of common bitumen mats 11a, which for example have a thermal conductivity of 20 W / mK, so that a significant energy saving can be achieved.

Expediently, the adhesive layer 13 has a modulus of elasticity of at least 20 N / mm ² , preferably of at least 100 N / mm ² , particularly preferably of at least 500 N / mm ² . The modulus of elasticity is the ratio of a surface-related force to the change in length of a material caused thereby. The elastic modulus is usually denoted by the symbol E and is expressed in Newtons per square millimeter (N / mm ² ). The values given may refer to values determined at normal pressure and at 20 ° C. Due to the intended high values of the modulus of elasticity of the adhesive layer 13 prevents the bottom trough 7 is vibrationally decoupled from the bitumen mat 11 a. In this way, a particularly good Entdröhnung and / or sound insulation of the floor pan 7 can be achieved.

Advantageously, the adhesive layer 13 consists of a hotmelt adhesive. Hot melt adhesives, also called hot-melt adhesives, are those adhesives which by Heating liquefied and applied in a liquid state, to establish a connection during cooling and solidification. Hotmelt adhesives result in a permanently stable connection between the base trough 7 and the bituminous mat 11a, whereby a strong oscillation coupling can also be achieved. In particular, hot melt adhesives may be based on polymers such as, for example, polyamides (PA), polyethylenes (PE), amorphous polyalphaolefins (APAO), ethylene-vinyl acetate copolymers (EVAC), polyester elastomers (TPE-E), polyurethane elastomers (TPE-U). , Copolyamide elastomers (TPE-A) and so forth. In the exemplary embodiment, the material of the hot melt adhesive is selected so that its processing temperature is below the melting temperature of the plastic of the bottom pan 7.
The adhesive layer 13 could alternatively consist of a reactive cured bituminous mixture.

The adhesive layer 13 is expediently delimited laterally by at least one delimiting element 14 projecting on the lower surface of the bottom trough 7, that is to say on the side of the bottom trough remote from the rinsing chamber interior. In this way, it is possible to prevent the adhesive from flowing away, or even dripping off, parallel to the outer surface of the bottom trough 7 before complete curing. In addition, the common contact surface of the bottom pan 7 and the adhesive layer 13 can be increased, so that the connection of the bottom pan 7 and adhesive layer 13 becomes more resilient. It can be provided that the adhesive layer 13 is partially bounded by the at least one projecting boundary element 14 or completely bordered. The limiting element 14 may in particular be formed as a web 14, whose height may exceed the height of the adhesive layer 13, whereby the bitumen mat 11a may be protected at its edge against external influences, for example in the manufacture of the dishwasher.

Conveniently, the bitumen mat 11a is glued to a three-dimensionally structured surface of the bottom tray 7. In this way, the contact surface of the bottom tray 7 can be further increased with the adhesive layer 13, so that the connection of the bottom tray 7 and adhesive layer 13 is even more resilient.

In this case, the structured surface in the embodiment webs 15. The webs 15 cause a three-dimensional structuring of the surface and can in particular on injection molded parts, such as the bottom tray 7, are easily formed. Alternatively, one or more grooves could be provided for structuring the surface. Expressed in general terms, one or more depressions and / or elevations or elevations on the outer surface of the respective component to be occupied by the bitumen mat, such as, for example, the underside of the bottom pan, may be expediently provided.

At least part of the micropores 16 can be produced by foaming a base material of the adhesive layer 13, for example by means of a foaming additive. Likewise, at least a portion of the micropores 16 may be made by introducing porous solids into the adhesive layer. Suitable for this purpose are, in particular, aerogels which are highly porous.

Advantageously, the floor pan 7 is entdröhnt and / or sound-insulated by a layer arrangement, which is formed exclusively by the bitumen mat 11 a and the adhesive layer 13. In this way, an effective and permanent Entdröhnung and / or soundproofing of the floor pan 7 can be effected in a simple manner. In principle, however, it would be possible to arrange a plurality of adhesive layers 13 and bitumen mats 11a stacked or stacked on the outside of the underside surface of the base trough.

The bitumen mat 11a preferably has a maximum thickness DBM in a range of 0.8 to 8 mm, preferably in a range of 1.2 to 6 mm, particularly preferably in a range of 1.6 to 4 mm. In the areas mentioned, sufficient sound insulation and / or soundproofing of the floor pan 7 of the dishwasher can be achieved with a low use of material. As shown, the bituminous mat 11a may have a constant thickness or a variable thickness.

Advantageously, the adhesive layer 13 has a maximum thickness DKS in a range of 0.1 to 6 mm, preferably in a range of 0.2 to 3 mm, particularly preferably in a range of 0.4 to 1.5 mm. In the above areas, the adhesive layer 13 is sufficiently thick to even in unwanted bumps and / or in a desired three-dimensional structuring of the surface of the bottom pan 7 and / or the surface of the bitumen mat 11 a full-surface contact of the adhesive layer 13 with the Floor pan 7 and / or to achieve with the bitumen mat 11a. As a result, a particularly stable arrangement is achieved with particularly good Entdröhnwirkung. In addition, a substantial reduction in the heat flow from the rinsing chamber 10 to the bitumen mat 11a is achieved. At the same time an excessive use of material is avoided.

Alternatively, according to a preferred embodiment, the adhesive layer 13 could consist of a reactively hardened bituminous mixture whose thermal conductivity is adjusted by the micropores 16 in accordance with the invention. The micropores 16 can be formed by intumescent additives in the bituminous mixture.

Reactively curable bituminous mixtures expediently include at least one base binder of bitumen, also called earth pitch, or of bitumen-type binders, which has such a high viscosity at an intended processing temperature that it behaves almost like a solid.

The base binder may be, for example, petroleum distillate bitumens, natural asphalts, polymer bitumens, tars, pitches, paraffins, natural or synthetic resins and / or distillation residues of fats and oils.

In order to be able to form the bituminous mixture into an adhesive layer 13, it expediently contains at least one fluxing agent which lowers the viscosity of the mixture to such an extent that it can flow at the intended processing temperature, ie behaves like a liquid. Fluxing agents are preferably low-volatility solvents, in particular low-volatile oils based on mineral oils, tar oils, vegetable and animal fats and oils, carboxylic acids, and nonvolatile technical plasticizers of synthetic polymers which remain in the bituminous mixture even after the bituminous mixture has cured, ie do not evaporate.

In order to cause the bituminous mixture to cure after the formation of the adhesive layer 13, at least one reactive additive for producing a physical and / or chemical effect which increases the viscosity of the mixture is expediently added to the mixture before the adhesive layer is formed. It can the Effect of the reactive additive to be set automatically by the reactive additive or by the additional addition of at least one activator in motion.

The reactive additive may, if appropriate in cooperation with the activator, in particular preferably irreversibly cancel the effect of the fluxing agent, for example by crosslinking, precipitation or by binding to the base binder.

The reactive additive may comprise, for example, chelating agents, acid anhydrides, alcohols, carboxylic acids, fatty amines, inorganic salts, cements, lime, gypsum, dolomite, ashes, slags, glasses, silica gels and / or alums.

The activator may in particular include water, glycols, fatty alcohols, surfactants, acids and alkalis, metal salts, sulfur, peroxides, latex and / or synthetic resins.

Furthermore, it may be expedient if the base binder, the flux, the reactive additive and / or the activator regenerative, ie renewable raw materials, especially vegetable or mineral raw materials are selected.

The adhesive layer 13 of the reactively cured bituminous mixture has superior adhesive properties both to the bitumen mat 11a-11f and to the usual surface materials of the wall parts in comparison to known adhesives for fixing bitumen mats 11a-11f to wall parts 2, 6, 7, 9 on dishwashers 2, 6, 7, 9 of dishwashers. In particular, the adhesive layer adheres to the wall part 7 made of plastic, in particular the plastic floor pan of the washing, particularly well. In particular, polypropylene may be chosen as the plastic. But even on wall parts 2, 6, 9 of bare metal, in particular made of bare stainless steel, a sufficiently strong adhesion adhesion of the bitumen mat can be ensured at the respectively to be occupied wall part.

Due to the good adhesive properties of the adhesive layer 13 of the reactively cured bituminous mixture can in most cases on a pretreatment of the surface of the wall part, such as roughening, Plasmatieren, flaming and the like, are dispensed with, which simplifies the production of the dishwasher.

In comparison with known hot-melt adhesives, which typically require a processing temperature of, for example, 130 ° C. to 200 ° C., the adhesive layer 13 can be made from the reactively cured bituminous mixture with suitable selection of the components without heat at room temperature, ie essentially "cold". , getting produced. In this way, a significant energy saving can be achieved in the manufacture of the dishwasher. This is particularly advantageous in heat-sensitive plastic components, which are each covered with one or more bitumen mats, because an impermissible thermal stress, thermal deformation or even melting of the plastic material of the respective component is avoided in an inadmissible manner. However, it may be useful to provide in the manufacture of the adhesive layer, a supply of heat to accelerate the curing. However, generally much lower temperatures, for example 60 to 70 ° C, are sufficient for this purpose.

In addition, by the use of the adhesive layer of the reactive cured bituminous mixture when attaching the bitumen mat 11a-11f to the wall part 2, 6, 7, 9, the thermal load of the entdröhnenden and / or sound-insulating wall part 2, 6, 7, 9, the Pre-assembled bitumen mat 11 a-11f and / or other components of the dishwasher are kept low. As a result, in many cases less temperature-stable components can be used than hitherto, which can reduce the manufacturing costs of the dishwasher.

Compared to the use of known cold adhesives which typically contain a volatile and curing solvent, the use of the adhesive layer 13 of the reactively cured bituminous mixture may be more environmentally friendly.

The adhesive layer 13 of the reactive cured bituminous mixture is also extremely durable and can thus outlast the useful life of a dishwasher in most cases.

In an advantageous embodiment of a dishwasher according to the invention, the Entdröhnfolien or bitumen mats are glued over a hot melt adhesive to the stainless steel structure of the washing. The adhesive layer is expediently equipped thermally insulating. Additives in the adhesive, such as aerogels or intumescent materials, can disrupt heat flow into the bitumen film.

As a result, an energy saving and thus a CO ₂ reduction can be achieved.

By means of the thermally insulating or blocking adhesive layer, improved thermal decoupling of the respective bitumen mat from the respective associated wall part and / or the inner wall of the door can be ensured. As a result, less heat energy from the interior of the washing container during the respective heating of a part program step of a selected dishwashing program, such as the cleaning cycle or rinse cycle, transported into the respective bitumen mat and stored there in their storage mass, that is, the washing container less heat energy than before removed in the conventional bonding of the bitumen mat by means of hot melt adhesive. By the thermally insulating adhesive layer, the energy efficiency of a dishwasher designed according to the invention can be improved. At the same time it is possibly even possible through the thermally insulating adhesive layer even to choose the basis weights and volumes of bitumen mats per dishwasher to improve the Entdröhnung the Spülbehälters or generally expressed the soundproofing of the dishwasher sufficiently large, although the bitumen mats, ie heavy layers, even as Heat storage medium act.

LIST OF REFERENCE NUMBERS

1

rinse tank

2

First wall part; Spülbehälterhaube

3

Side wall

4

Side wall

5

blanket

6

Second wall part; rear wall

7

Third wall part; floor pan

8th

door

9

Fourth wall part; interior door

10

rinsing chamber

11

bitumen mat

12

sump

13

adhesive layer

14

limiting element

15

web

16

micropores

DBM

Maximum thickness of the bitumen mat

DKS

Maximum thickness of the adhesive layer

Claims (12)

1. Dishwasher, in particular domestic dishwasher, having at least one wall section (2, 6, 7, 9) for delimiting a washing chamber (10), which is provided with at least one bitumen pad (11a to 11f) for muffling and/or sound-proofing the wall section (2, 6, 7, 9), wherein the bitumen pad (11a to 11f) is glued to the wall section (2, 6, 7, 9) by means of at least one, in particular purely precisely one, thermally insulating adhesive layer (13), which wall section has a lower heat conductivity than the bitumen pad (11a to 11f), characterised in that the adhesive layer (13) has micropores (16) and that the portion of the micropores (16) in the volume of the adhesive layer (13) amounts to at least 80%, preferably at least 90%, particularly preferably at least 95%.
2. Dishwasher according to the preceding claim, characterised in that the heat conductivity of the adhesive layer (13) amounts at most to 60%, preferably at most to 40%, particularly preferably at most to 20% of the heat conductivity of the wall section (2, 6, 7, 9).
3. Dishwasher according to one of the preceding claims, characterised in that the heat conductivity of the adhesive layer (13) amounts at most to 0.12 W/mK, preferably at most to 0.08 W/mK, particularly preferably at most to 0.04 W/mK.
4. Dishwasher according to one of the preceding claims, characterised in that the adhesive layer (13) has an elasticity module of at least 20 N/mm², preferably of at least 100 N/mm², particularly preferably of at least 500 N/mm².
5. Dishwasher according to one of the preceding claims, characterised in that the adhesive layer (13) consists of a hot melt adhesive.
6. Dishwasher according to one of claims 1 to 4, characterised in that the adhesive layer (13) consists of a reactively cured bituminous compound.
7. Dishwasher according to one of the preceding claims, characterised in that the adhesive layer (13) is laterally delimited by at least one delimiting element (14) projecting onto the wall section (2, 6, 7, 9).
8. Dishwasher according to one of the preceding claims, characterised in that the bitumen pad (11a to 11f) is glued to a three-dimensionally structured surface of the wall section (2, 6, 7,9).
9. Dishwasher according to the preceding claim, characterised in that the structured surface has at least one web (15) and/or at least one groove.
10. Dishwasher according to one of the preceding claims, characterised in that the wall section (2, 6, 7, 9) is muffled and/or soundproofed by a slice arrangement (11a to 11f, 13), which is formed exclusively by the bitumen pad (11a to 11f) and the adhesive layer (13).
11. Dishwasher according to one of the preceding claims, characterised in that the bitumen pad (*11a to 11f) has a maximum thickness (DBM) in a range of 0.8 to 8 mm, preferably in a range of 1.2 to 6 mm, particularly preferably in a range of 1.6 to 4 mm.
12. Dishwasher according to one of the preceding claims, characterised in that the adhesive layer (13) has a maximum thickness (DKS) in a range of 0.1 to 6 mm, preferably in a range of 0.2 to 3 mm, particularly preferably in a range of 0.4 to 1.5 mm.

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