ES2610976B1 - Dishwasher machine - Google Patents

Abstract

The invention refers to a dishwashing machine (1), in particular, to a domestic dishwashing machine, with a washing chamber (4) for housing the washing articles and with a heat insulating layer (15), which partially or partially surrounds complete to the washing chamber (4) and whose thermal conductivity is adjustable depending on the operating state of the dishwasher machine (1), in particular, of the domestic dishwasher machine, where the thickness (D) of the heat insulating layer (15 ) is modifiable for thermal conductivity adjustment.

Description

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DISHWASHER MACHINE

DESCRIPTION

The present invention refers to a dishwasher machine, in particular, to a domestic dishwasher machine.

The dishwasher machines, namely, the domestic dishwasher machines, known have a washing chamber to house the washing articles. Depending on the washing program chosen, different time-dependent operating conditions occur in the washing chamber, in which basically the heating items are cleaned, cleaned, and the washing articles are dried. These steps are related to the supply and extraction of thermal energy to and from, respectively, the washing chamber. Therefore, known dishwasher machines have a heat insulating layer that partially or completely surrounds the washing chamber. In this way, thermal energy is conserved in the washing chamber during the cleaning process, so that the energy requirement of the dishwasher is reduced. However, during the drying process it is desirable that the thermal energy present in the washing chamber can be removed in a controlled manner to dehumidify the wet air mixture in the washing tank during the drying process as quickly as possible. and therefore accelerate drying.

Through the patent application DE 103 46 964 A1, a dishwashing machine is known, in particular a domestic dishwashing machine, which has a heat insulating layer with variable thermal conductivity. The thermal conductivity is adjustable in at least two different values of thermal conductivity. In this way, in a first state of operation of the dishwasher, heat can be expelled from the washing chamber quickly, while, in a second state of operation of the dishwasher, it is kept in the washing chamber. The different values of thermal conductivity are achieved in this state of the art by understanding the thermal insulating layer a capsule with hydrogen in which a metal hydride network is arranged, which can form a chemical compound with hydrogen.

The present invention solves the technical problem of providing a dishwasher machine, in particular, a domestic dishwasher machine, which uses an alternative approach to provide an adjustable thermal conductivity.

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Accordingly, a dishwashing machine is provided, in particular, a domestic dishwashing machine, with a washing chamber to house the washing articles and with a heat insulating layer, which partially or completely surrounds the washing chamber and whose thermal conductivity It is adjustable depending on the operating status of the dishwasher, in particular the domestic dishwasher. The thickness of the heat insulating layer is modifiable for the adjustment of thermal conductivity.

The idea on which the present invention is based is to modify the geometry of the heat insulating layer in order to adjust the thermal conductivity of the heat insulating layer. This modification of the geometry first comprises a modification of the thickness of the heat insulating layer. However, together with this, also the other two dimensions, that is, the length and width, of the heat insulating layer can be provided to be adjustable depending on the operating state of the dishwasher, in particular, of the domestic dishwasher.

The term "operating status" of the dishwasher includes the concept of a state that the dishwasher presents during the execution of an operation program thereof. The operation program may comprise a cleaning process and / or a drying process , in which the washing articles are cleaned or dried, respectively, in the washing chamber.The operation program may be provided in a control device of the dishwasher machine.The control device may have a microprocessor and a data storage, where the operating program is stored in the latter.

According to one embodiment, the heat insulating layer is partially or completely composed of a flexible material.

In this way, the heat insulating layer can be partially or completely deformed to thereby adjust its thickness to the desired extent. Preferably, the flexible material is also elastic. The heat insulating layer can be compressed and / or expanded for the desired thickness modification.

According to another embodiment, the flexible material is porous.

A porous material is characterized mainly because, when compressed or expanded, there is a change in its thermal conductivity.

According to another embodiment, the flexible and porous material is a polymer foam.

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The polymer foam may have polypropylene or polyethylene. These materials may be provided with the desired flexibility and porosity. The polymer foam may have an open pores or closed pores material. The pores may be filled with gas, specifically, air.

According to another embodiment, a pressure application device is provided, which is configured to apply pressure to the flexible material to compress and / or expand it.

As a consequence of the applied pressure, the heat insulating layer modifies its thickness, so that its thermal conductivity is modified accordingly. The pressure application device may be coupled with the control device mentioned above, so that the pressure application device adjusts the thickness of the heat insulating layer depending on a control signal of the control device.

According to another embodiment of the pressure application device, it is configured to apply the pressure to the flexible material by means of a fluid.

The fluid may be a liquid and / or a gas, preferably air. Being the fluid introduced under pressure in the flexible material, it widens, thereby increasing its thickness. Conversely, the fluid can also be extracted from the flexible material to reduce its thickness. Alternatively, an inflatable body can be filled with the fluid, which then expands and exerts a corresponding pressure on the flexible material, so that it is compressed. Similarly, the fluid can be removed again from the inflatable body, whereby the flexible material can expand again.

According to another embodiment, the pressure application device has a fluid pump, which is configured to supply the fluid to the flexible material to expand the flexible material, and to evacuate the fluid from the flexible material to compress the flexible material.

The fluid pump can be, for example, a gear pump, a plunger pump, or a centrifugal pump.

According to another embodiment, the pressure application device has a mechanical element, which is movable to compress or expand the flexible material.

Therefore, in this embodiment (unlike the previous embodiment) the flexible material is acted upon by a solid body (mechanical element). The element

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mechanical can be, for example, a seal, a pushing device, or an iron. The mechanical element may also comprise a mechanism that is configured to move towards each other or by separating them from an inner wall and an outer wall between which the heat insulating layer is arranged, to thereby adjust the thickness of the heat insulating layer. The heat-insulating layer may be disposed loose between the inner and outer wall, that is, in the corresponding recess, or it may be attached, in particular, glued to them, for example, by opposite front surfaces, so as to follow the movement relative of the inner and outer wall. On the other hand, the heat-insulating layer may be housed in the first case being pressed between the inner and outer wall, so that it follows a relative movement of the inner and outer wall with each other, without being fixedly attached, in concrete, stuck, with these.

According to another embodiment, the heat insulating layer is made between an inner and an outer wall of the washing chamber, where a gap between the inner and outer wall has a width that varies depending on the thickness of the heat insulating layer, where a Flexible joint closes the gap.

Advantageously, the seal can therefore accompany the relative movement of the inner and outer wall. The gasket is fluid tight, preferably gas tight. This particularly concerns those applications in which a gas, for example, air, is pumped into the flexible material. This effect can also be achieved by pumping the gas only into the hole between the inner and outer wall. In this case, the gas then diffuses into the porous material, after which it expands. Therefore, the joint can be responsible for sealing the defined volume between the inner and outer wall for different widths of the gap.

According to another embodiment, the heat insulating layer has a shape memory material, which modifies its thickness as a function of temperature.

Therefore, the shape memory material, or the heat insulating layer, has a thickness

determined at a certain temperature. Consequently, the heat insulating layer

controls its thickness automatically, that is, without being dependent on the device

control mentioned above. Advantageously, a heat insulating layer of this

type also does not need power supply for the modification of its thickness. The

energy required for the modification of its thickness can be extracted from thermal energy

present in the washing chamber. In an alternative embodiment, the material of

shape memory can also change its thickness depending on the electrical voltage

that is being applied to shape memory material. As memory materials of

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Appropriate forms are considered SMM PU (Form Memory Material based on Polyurethane) or nitinol. These materials may have, for example, a density of 6 g / cm3, a thermal conductivity of 0.1 W / (cm x ° C), a specific heat of 0.2 cal / (gx ° C), and an extension 5% transitory. The heat insulating layer, or the flexible material, can also be filled with an additive to improve its thermal and / or acoustic properties.

Likewise, a dishwashing machine with a washing chamber is proposed to house the washing articles, with an insulation hole that partially or completely surrounds the washing chamber, and with a bridging device to bridge the insulation hole in dependence. of the operating status of the dishwasher, which comprises a thermoconducting material.

Accordingly, the bridging device has a first state in which it bridges the insulation gap and, thereby, provides a high thermal conductivity, as well as a second state, in which it does not bridge the insulation gap and, thereby, The insulating action of the insulation gap takes effect, so that a low thermal conductivity results.

The operating states of the dishwasher can be defined as described above.

As a thermally conductive material, metal, for example, steel plate, or aluminum, is considered.

According to another embodiment, the bridging device is switchable between at least a first and a second state, where it, in the first state, thermoconductively joins the opposite walls of the dishwasher, which delimit the insulation gap and, in the second state, thermally decouple the walls from each other.

The walls may comprise an inner wall and an outer wall of the dishwasher. The gap may present a vacuum. As an alternative, the hole can have a gas, for example, air.

According to another embodiment, the bridging device has a shape memory material, which switches between the first and second state automatically and dependent on temperature.

In this way, an electronic activation of the bridging device can be dispensed with. The shape memory material, specifically, a shape memory alloy, modifies

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its geometry when staying above, or, when staying below, a predefined limit temperature. In one embodiment, the thermally conductive material is made partially or completely by the shape memory material. In another embodiment, the shape memory material is used as a drive element to switch the bridging device between the first and second state.

According to another embodiment, the bridging device is pivotable or foldable between the first and the second state.

Instead of a dishwasher machine, the present invention could also be applied in a washing machine or in a refrigerator. Instead of the washing chamber, the washing machine has a washing drum or other housing for the washing articles, and the refrigerator has a refrigeration compartment or other housing for the refrigeration products.

Other possible implementations of the invention also comprise combinations not explicitly mentioned of features or embodiments described above, or below, in relation to the embodiments. Here, the person skilled in the art will also add particular aspects such as improvements or complements to the respective basic form of the invention.

Other configurations and advantageous aspects of the invention are the subject of the secondary claims, as well as the embodiments of the invention described below. Next, the invention is explained in more detail by means of preferred embodiments, with reference to the attached figures.

They show:

Fig. 1

a perspective view of an embodiment of a dishwasher machine;

Fig. 2A in a section II-II of figure 1, a heat insulating layer of the dishwasher, in a first operating state thereof;

Fig. 2B the view of figure 2A, in a second state of operation of the dishwasher;

Fig. 3

section II-II of figure 1, although with a bridging device according to an embodiment; Y

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Fig. 4 the bridging device of Fig. 3 according to another embodiment.

In the figures, the same or equal function elements are accompanied by the same reference symbols, as long as nothing else is indicated.

Figure 1 shows a perspective view of a household water-conducting appliance in the form of a dishwashing machine 1, in particular of a domestic dishwashing machine. Instead, the household appliance could also be, for example, a washing machine, a refrigerator, or the like.

The dishwashing machine 1 has a washing tank 2, which is water tightly locked by a door 3. The washing tank 2 is made, for example, in the shape of a parallelepiped, together with the door 3 it defines a chamber of washing 4 to wash the washing articles, and may be arranged inside a rack of the dishwasher 1 not shown.

Door 3 is shown in Figure 1 in its open position. The door 3 can be closed or opened by being rotated around a pivoting axis 5 provided at the lower end of the door 3. The washing tank 2 has a wall 6 with a floor 7, a cover 8 arranged in front of the floor 7, a rear wall 9 arranged in front of the closed door 3, and two side walls 10, 11 arranged opposite each other. The floor 7, the cover 8, the rear wall 9, and the side walls 10, 11 can be made, for example, of one or more steel sheets. Alternatively, the floor 7 can be made, for example, of a plastic material.

In addition, the dishwasher 1 has at least one housing for washing items 12 to 14. In particular, several housings for washing items 12 to 14 may be provided, a lower basket 12, an upper basket 13 and / or a cutlery drawer 14. The housings for washing articles 12 to 14 are preferably arranged one above the other in the washing tank 2. Each of the housings for washing articles 12 to 14 is optionally movable to the interior or to the outside the wash tank 2. This can occur in the insertion direction E or in the extraction direction A, respectively.

Figure 2A shows in a section II-II of Figure 1 a heat insulating layer 15 of the dishwashing machine 1.

The heat insulating layer 15 can be integrated in the side wall 11 (right in figure 1) of the washing tank 2, and can be arranged in particular between an inner wall 16

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and an outer wall 17 of the side wall 11. Also the opposite side wall 10 may have a heat insulating layer 15, as is being explained by way of example only for the side wall 11.

The inner wall 16 can be here directed towards the washing chamber 4, in particular, it can be delimited by sections. On the contrary, the outer wall 17 can be separated from the washing chamber 4 and directed towards a frame 18 of the dishwasher 1 which is not described in more detail or towards the surroundings U of the surrounding dishwasher 1. The heat insulating layer 15 thus surrounds the washing chamber 4 at least partially.

The heat-insulating layer 15 can be made of a flexible material, that is, reversibly deformable, or also elastic, and can in particular have a porous material. By way of example, a heat insulating layer 15 that is partially or completely formed of polymer foam, in particular polypropylene or polyethylene foam, is suitable.

The heat insulating layer 15 has an adjustable thermal conductivity depending on the operating state of the dishwashing machine 1. The thermal conductivity can be provided here by being adjustable between at least two values, preferably with continuous progression. The objective is, for example, in a first state of operation of the dishwashing machine, to provide a high first thermal conductivity to guarantee a high heat transport W from the washing chamber 4. This may be desirable, for example, in a state of operation of the dishwasher machine 1 during a drying process, when the washing articles are dried in the washing chamber 4. In addition, the heat insulating layer 15 has a second low thermal conductivity in a second operating state of the dishwasher machine 1, for example, during a cleaning process. In the second operating state, little heat transport W takes place through the heat insulating layer 15 (see Figure 2B). In general, the first thermal conductivity in the first operating state is greater than the second thermal conductivity in the second operating state. In particular, the first thermal conductivity may be more than twice, preferably more than five times and, more preferably, more than ten times greater than the second thermal conductivity.

To provide the different thermal conductivities, the thickness D of the heat insulating layer 15 is modified. Additionally, other geometric modifications of the heat insulating layer 15 can also be made that contribute to the modification of the

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thermal conductivity of the heat insulating layer 15, for example, also of its width and height.

The modification of the thickness D of the heat insulating layer 15 can occur in different ways described below. These are also expressly combinable with each other.

According to a first embodiment, the heat insulating layer 15 is made of a material that modifies its thickness D depending on the temperature. In particular, the heat insulating layer 15 may be made of a shape memory material. If the temperature of the heat-insulating layer 15 thus formed exceeds, or, if the temperature of the washing chamber 4 correspondingly exceeds a defined limit value, then the thickness D of the heat-insulating layer 15 is modified (almost instantaneously) . For this purpose, the heat insulating layer 15 may be formed by SMP PU (Polyurethane-based Shape Memory Polymer) or nitinol. The limit temperature can be found here, for example, in a temperature range of between 70 and 80 ° C, preferably, at 75 ° C. The density of the shape memory material can be, for example, 6 g / cm3, thermal conductivity, at 0.1 W / (cm x ° C), specific heat, at 0.2 cal / (gx ° C), and transient deformation, at 5%. The shape memory material or, what is the same, the heat insulating layer 15, can also be filled with other materials to improve their thermal and / or acoustic properties.

In the first embodiment described above, it is advantageous that an electronic control device is not necessary to direct the thickness D of the heat insulating layer 15. In fact, the modification of the thickness D occurs automatically when it is over or over. below the defined limit temperature.

According to a second and a third embodiment (shown in a continuous and discontinuous line, respectively), the modification of the thickness D of the heat insulating layer 15 is carried out by means of a pressure application device 19. Generally speaking, the application device for Pressure 19 is configured to apply pressure to the heat insulating layer 15 to compress or expand it. The term "pressure" also includes the concept of a negative pressure. In a possible embodiment, a gas, in particular air, can be introduced here under pressure into the pores of the heat insulating layer 15, or it can be applied A vacuum to these.

The heat insulating layer 15 can be incorporated between the inner and outer wall 16, 17 being prestressed so that it is always in direct contact with the inner wall and the

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exterior 17 having a variable distance between them. Alternatively, the heat insulating layer 15 can be glued to the inner wall 16 and the outer wall 17 by their respective large surface front sides.

In the second embodiment (continuous line representation), a fluid, in particular, air, is used to apply pressure (or negative pressure) to the flexible material, that is, to the heat-insulating layer 15 and, thus, modify its thickness D. In this exemplary embodiment, the pressure application device 19 is made as a fluid pump 20, in particular, as an air compressor. The fluid pump 20 can pump the fluid into the hole 21 between the inner wall 16 and the outer wall 17, after which the fluid, in particular, the air, diffuses into the interior of the heat insulating layer 15 and the fan. Similarly, the fluid pump 20 can also apply a vacuum, which then causes contraction or compression of the heat insulating layer 15. Alternatively, the fluid pump 20 can directly pump the fluid into the heat insulating layer 15 or extract it from it. According to another embodiment, an inflatable body 22 is shown in dotted line and discontinuous in Figure 2A, which is inflated or emptied by the fluid pump 20. The inflatable body 22 exerts pressure on the heat insulating layer 15 to compress it, or contract it, after which the heat insulating layer 15 expands thanks to its elasticity. The inflatable body 22 is represented in dotted lines and discontinuous and is accompanied by the reference symbol 22.

The pressure application device 19 can be technically coupled by means of signals with a control device 23 of the dishwashing machine 1. Depending on the operating state, for example, during a drying or cleaning operation, the control device 23 activates the pressure application device 19 so that pressure is applied to the heat insulating layer 15 for the corresponding modification of its thickness D and, thereby, the modification of its thermal conductivity. The control device 23 may have a microprocessor and a memory. One or more cleaning programs may be stored in memory. A corresponding cleaning program comprises theoretical values for the thermal conductivity of the desired heat insulating layer 15 in a respective operating state. The activation of the pressure application device 19 occurs depending on these theoretical values.

In order to prevent the fluid from leaving the gap 21 between the inner wall 16 and the outer wall 17 forward in the direction of the door 3, a flexible joint 24 may be provided, which is fixedly sealed to the inner wall 16, on the one hand

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outer wall 17, on the other hand. The joint 24 can be made elastically, for example, in the form of a bellows, and is configured to follow the relative movement of the inner and outer wall 16, 17, that is, to take into account the different width of the gap.

According to a third embodiment (shown in broken lines in Figure 2A and in Figure 2B), instead of the pressure application device 19 in the form of a fluid pump 20, a mechanical element 25 may be provided, for example, a pushing device (as shown), a plunger, or an iron that acts indirectly (here, by the outer wall 17) or directly (not shown) on the heat insulating layer 15 in the direction of its thickness to compress it or expand it

By way of example, together with the mechanical element 25, the pressure application device 19 can have an actuator 26, for example, in the form of an electric motor. The actuator 26 drives the mechanical element 25 to expand or compress the heat insulating layer 15. According to the exemplary embodiment shown, the thrust device 25 may have a rack section 27, which is engaged with a cogwheel 28. The cogwheel 28 may in turn be driven by the electric motor 26. By way of example, the sprocket 28 can be rotated in the direction of the arrow shown in Figures 2A and 2B against the clockwise direction to move the thrust device 25 from left to right. In this way, the thickness D of the heat insulating layer 15 is increased, correspondingly reducing its thermal conductivity.

Figure 3 also shows section II-II of Figure 1, although with a bridging device 29 instead of the heat insulating layer 15.

In the exemplary embodiment according to FIG. 3, the side wall 11 comprises an insulation gap 30 between the inner wall 16 and the outer wall 17. The insulation hole 30 partially or completely surrounds the washing chamber 4, can be extended all over the side wall 11, and may present a vacuum. In this case, a gasket 31 can be provided that seals the insulation gap 30 with respect to the environment U. The gasket 31 can be provided next to a front side of the side wall 11 directed towards the door 3.

The bridging device 29 serves to bridge the insulation gap 30 depending on the operating state of the dishwashing machine 1, and has a thermally conductive material, for example, a metal.

Figure 3 shows in a continuous line a first state and, in a broken line, a state

second of the bridging device 29. In the first state, the bridging element 29 joins

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thermoconductively the walls 16, 17 that delimit the insulation gap 30. In the second state, the bridging element 29 is pivoted to a position in which the two walls 16, 17 are thermally disengaged.

For this, the bridging device 29 can have, for example, two arms 32, 33, which are installed next to an axis 34. The axis 34 can be driven by an actuator 35, for example, an electric motor. The actuator 35 may be technically coupled by means of signals with the control device 23 already described in relation to Figures 2A and 2B. The control device 23 activates the actuator 35 depending on the theoretical values of the thermal conductivity through the insulation gap 30. These theoretical values are contained in one or more cleaning programs stored in the control device 23.

Finally, Figure 4 shows a variant with respect to Figure 3. The bridging device 29 is here realized as a shape memory material, in particular, a shape memory alloy. This automatically switches between a first and a second state depending on the temperature present in the insulation hole 30, or on the corresponding temperature present in the washing chamber 4. The first state is shown in Figure 4 in continuous line and, the second state, in a broken line.

In the first state, the bridging device 29 comes into contact at its free end with a thermoconductive section 36 at its free end, and thus bridges the hollow 30 in a thermoconductive manner. The thermoconductive section 36 is also formed by metal, for example, aluminum.

When a defined limit temperature is exceeded, for example, within the framework of a cleaning process in the washing chamber 4, at 75 ° C, the bridging device 29 or, what is the same, the material of its memory alloy so, it deforms (virtually instantaneously), so that the thermal bridge through the insulation gap 30 is interrupted. Then, the side wall 11 correspondingly has a low thermal conductivity. The bridging device 29 and the thermoconductive section 36 can be made in each case in the form of curved bars. Opposite to its free end, the bridging device 29 is fixed in a thermoconductive manner, namely, in conjunction with material, for example to the outer wall 17, and the thermoconductive section 36 is opposite it to its free end the inner wall 16.

Although the present invention has been described by means of preferred embodiments, it is not limited thereto, but is variously modifiable.

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REFERENCE SYMBOLS

Dishwasher machine; domestic dishwasher machine

Washing tank

Door

Washing chamber Pivot axis Wall Floor Cover Rear wall Side wall Side wall

Accommodation for washing items

Accommodation for washing items

Accommodation for washing items

Heat insulating layer

Inner wall

Exterior wall

Frame

Pressure application device

Fluid pump

Hole

Inflatable body Control device Seal

Mechanical element Actuator

Rack section

Cogwheel

Bridging device

Insulation gap

meeting

Arm

Arm

Axis

35 Actuator

36 Heat Conductor Section

A Extraction Direction

D thickness

E Insertion Address

II-II Section

W heat transport

Claims (15)

5 10 fifteen twenty 25 30 35 1. Dishwashing machine (1), in particular, domestic dishwashing machine, with a washing chamber (4) to house the washing articles and with a heat insulating layer (15), which partially or completely surrounds the washing chamber (4) and whose thermal conductivity is adjustable depending on the operating status of the dishwashing machine (1), in particular, of the domestic dishwashing machine, where the thickness (D) of the heat insulating layer (15) is modifiable for adjustment of thermal conductivity. 2. Dishwashing machine (1) according to claim 1, characterized in that the heat-insulating layer (15) is partially or completely composed of a flexible material. 3. Dishwasher machine (1) according to claim 2, characterized in that the flexible material is porous. 4. Dishwashing machine (1) according to claim 3, characterized in that the flexible and porous material is a polymer foam. 5. Dishwasher machine (1) according to one of claims 2 to 4, characterized by a pressure application device (19), which is configured to apply pressure to the flexible material (15) to compress or expand it. 6. Dishwasher machine (1) according to claim 5, characterized in that the Pressure application device (19) is configured to apply pressure to the flexible material (15) by means of a fluid. 7. Dishwashing machine (1) according to claim 6, characterized in that the Pressure application device (19) features a fluid pump (20), which is configured to supply the fluid to the flexible material (15) to expand the flexible material (15), and to evacuate the fluid from the flexible material (15 ) to compress the flexible material (15). 8. Dishwasher machine (1) according to claim 5, characterized in that the Pressure application device (19) has a mechanical element (25), which is movable to compress or expand the flexible material (15). 5 10 fifteen twenty 25 30 35 9. Dishwashing machine (1) according to claim 8, characterized in that the mechanical element (25) acts directly or indirectly on the flexible material (15). 10. Dishwashing machine (1) according to one of claims 1 to 9, characterized in that the heat-insulating layer (15) is made between an inner and an outer wall (16, 17) of the washing chamber (4), where a gap (21) between the inner and outer wall (16, 17) has a width that varies depending on the thickness (D) of the heat insulating layer (15), where a flexible joint (24) closes the gap (21). 11. Dishwashing machine (1) according to claim 1, characterized in that the heat-insulating layer (15) has a shape memory material, which modifies its thickness (D) as a function of temperature. 12. Dishwashing machine (1), in particular, domestic dishwashing machine, with a washing chamber (4) to house the washing articles, with an insulating hole (30) partially or completely surrounding the washing chamber ( 4), and with a bridging device (29) for bridging the insulation gap (30) depending on the operating state of the dishwashing machine (1), in particular, of the domestic dishwashing machine, where the bridging element ( 29) comprises a thermally conductive material. 13. Dishwashing machine (1) according to claim 12, characterized in that the bridging device (29) is switchable between at least a first and a second state, where it, in the first state, thermoconductively joins the walls (16, 17) opposite the dishwasher (1), which delimit the insulation gap (30) and, in the second state, thermally decouple the walls from each other (16, 17). 14. Dishwashing machine (1) according to claim 13, characterized in that the bridging device (29) has a shape memory material, which switches between the first and second state automatically and dependent on temperature. 15. Dishwashing machine (1) according to claims 13 or 14, characterized in that the bridging device (29) is pivotable or foldable between the first and second state.