WO2017037553A1

WO2017037553A1 - Method for manufacturing a household appliance component comprising a base element

Info

Publication number: WO2017037553A1
Application number: PCT/IB2016/054478
Authority: WO
Inventors: Maria Carmen Artal Lahoz; Cristian Lavieja Belanche; Elena Martinez Solanas; David Urrutia Angos
Original assignee: BSH Hausgeräte GmbH
Priority date: 2015-09-01
Filing date: 2016-07-27
Publication date: 2017-03-09
Also published as: ES2603785A1; ES2603785B1

Abstract

The invention relates to a method for manufacturing a household appliance component 1, in which a base element 2is provided, wherein at least one micro channel 4for defining a flow path for fluids is generated in a surface 3 of the base element 2.The invention also relates to a household appliance component 1.

Description

METHOD FOR MANUFACTURING A HOUSEHOLD APPLIANCE COMPONENT COMPRISING A BASE ELEMENT

The invention relates to a method for manufacturing a household appliance component, a household appliance component, comprising a base element having a surface, and a household appliance comprising at least one household appliance component.

Household appliances like washing machines and dishwashers usually comprise pipes, tubes, conduits and the like in order to transport fluids between different sections of the household appliance. However, pipes, tubes and so forth to conduct fluids are sometimes oversized compared to the volume of the fluid to be transported. Fluids can for example be water, steam, oil, detergents and the like. Further, there are special applications in some household appliances in which standard pipes, tubes, or conduits are not suitable because the fluid to be dispensed does not have the necessary volume. In that case, the fluid usually cannot be transported from the inlet to the outlet of the pipe and instead remains on the inner walls of the pipe without reaching its destination. Depending on the fluid to be dispensed, this may lead to functional disorders or the need to employ more volume of the respective fluid than necessary. It is the task of the present invention to provide a method for manufacturing a household appliance component with enhanced performance characteristics concerning the routing of fluids. A further task of the invention consists in providing a household appliance component with enhanced performance characteristics concerning the routing of fluids. Still further, it is an object of the current invention to provide a household appliance comprising at least one household appliance component with enhanced performance characteristics concerning the routing of fluids.

These tasks are solved by a method, a household appliance component, and a household appliance according to the independent claims. Advantageous developments of the invention are specified in the respective dependent claims, wherein advantageous developments of the method are to be regarded as advantageous developments of the household appliance component and the household appliance and vice versa. A first aspect of the invention relates to a method for manufacturing a household appliance component, in which a base element having a surface is provided, wherein at least one micro channel for defining a flow path for fluids is generated in the surface of the base element. Micro channels in the context of the present invention are channels with a hydraulic diameter below approximately 1 mm and can be used for moving, mixing, condensing, separating, or otherwise processing fluids by defining a flow path. In contrast to pipes, tubes and the like, micro channels are generally open in two dimensions and can thus be also denoted as grooves. Micro channels can be used to transport or dispense small volumes of water, oil, detergents, or other fluids. Additionally, there are other applications where open micro channels allow the condensation of gases in order to further process the condensed liquids, which is usually not possible with closed pipes. The appliance component may comprise one or more micro channels at least in one or more portions of its surface or may comprise one or more micro channels arranged over its entire surface.

In an advantageous development of the invention it is provided that a plurality of micro channels is generated in the surface. The number of micro channels can be optimally adapted to the expected fluid volume. In a further advantageous development of the invention it is provided that the at least one micro channel is generated by at least one method selected from Nanoimprint Lithography (NIL), Micro-contact Printing (μCΡ), Step and Flash Imprint (SFIL), Roll-to-roll (R2R), Optical Lithography, Laser Lithography, Laser Interferometry, Extreme Ultraviolet Lithography (EUV), Focus Ion Beam Lithography (FIB), Ion Milling, Chemical etching, Dry plasma etch processing (DRIE), Dry etching, Reactive Ion Etching (RIE), Plasma Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), Plasma Enhance Chemical Vapor Deposition (PECVD), Atomic Force Microscope (AFM), Scanning Tunneling Microscopy (STM), Atomic Force Microscopy (AFM), Dip-Pen Nanolithography (DPN) and Electronic Beam Lithography (EBL). This allows for a very flexible and precise manufacturing of one or more micro channels in consideration of the geometry of the channel(s) and the current material of the surface. If the surface of the base element is for example made of stainless steel, optical lithography (photolithography) and/or ion milling can be used to create one or more micro channels. In a further advantageous development of the invention it is provided that a base element having a coating is used and in that the at least one micro channel is generated in the surface of said coating. The one or more micro channels in other word can not only be generated directly in the surface of the base element (substrate) but also in the surface of a coating of the base element (substrate). The coating can be used to provide the base element with additional functionalities.

In a further advantageous development of the invention it is provided that the coating is selected from one or more of superhydrophobic coatings, superoleophobic coatings, and superhydrophilic coatings. This allows for an optimal adjustment of the surface properties of the household appliance component for a wide range of application purposes and installation settings. For the generation of superhydrophobic coatings for example SiO₂ derivatives like methylated silica in ethanol, polysiloxane-urethane inorganic-organic coatings, silicone polyester in n-butyl acetate, fluoropolymer compounds derivatives like ethylacetate fluoroalkyl functional water-borne oligosiloxanes, ethyl and methyl nonaflourobutyl ether, Al₂0₃ derivatives, and TiO₂ derivatives may be used. Superoleophobic coatings may be formed using fluoropolymer compound derivatives like ethylacetate fluoroalkyl functional water-borne oligosiloxanes, ethyl- and methyl- nonaflourobutyl ether and others. Superhydrophilic coatings may be manufactured using TiO₂ derivatives like titanium dioxide with ethanol as solvent, or organic solvent based or resin-bonded SiO₂ derivatives.

A second aspect of the invention relates to a household appliance component, comprising a base element having a surface, wherein the base element comprises at least one micro channel for defining a flow path for fluids. Micro channels in the context of the present invention are channels with a hydraulic diameter below approximately 1 mm and can be used for moving, mixing, condensing, separating, or otherwise processing fluids by defining a flow path. In contrast to pipes, tubes and the like, micro channels are generally open in two dimensions and can thus be also denoted as grooves. Micro channels can be used to transport or dispense small volumes of water, oil, detergents, or other fluids. Additionally, there are other applications where open micro channels allow the condensation of gases in order to further process the condensed liquids, which is usually not possible with closed pipes. The appliance component may comprise one or more micro channels at least in one or more portions of its surface or may comprise one or more micro channels arranged over its entire surface. Further features and their advantages can be gathered from the description of the first aspect of the invention. Advantageous embodiments of the first aspect of the invention are to be regarded as advantageous embodiments of the second aspect of the invention and vice versa.

In an advantageous development of the invention it is provided that the household appliance component is manufactured by a method according to the first aspect of the invention. In a further advantageous development of the invention it is provided that the at least one micro channel has a maximum hydraulic diameter of less than 1 mm, in particular of less than 500 μηι, and preferably of less than 50 μm. A maximum hydraulic diameter of less than 1 mm may comprise diameters of

or less, wherein respective intermediate values are to be regarded as being comprised and disclosed by the invention, too. Alternatively or additionally it is provided that the at least one micro channel has a maximum height of less than 1 mm, in particular less than 100 μm. The preferred maximum height may thus have values of

or less, wherein respective intermediate

values are to be regarded as being comprised and disclosed by the invention, too. These geometric features, independently of each other, allow for a very precise definition of flow paths and flow behaviour of fluids, depending for example on their volume, viscosity and aggregate state. In a further advantageous development of the invention it is provided that the at least one micro channel has a uniform or non-uniform cross-sectional geometry along its axial direction. In other words it is provided that the at least one micro channel has a constant or a varying geometry along its entire length. This geometric feature also allows for a very precise definition of the flow behaviour of fluids along the micro channel.

In a further advantageous development of the invention at least two micro channels are provided, wherein adjacent micro channels are spaced between 5 μm and 50 μm from one another. This means that the spacing between neighbouring micro channels is 5 μm,

In a further advantageous development of the invention it is provided that the at least one micro channel at least in sections has a semicircular or polygonal cross-sectional geometry. This allows for a precise adjustment of the flow behaviour of fluids along the micro channel. The polygonal cross-sectional geometry may for example have 3, 4, 5, 6, 7, 8, 9, or more edges and may be a regular or an irregular polygon.

In a further advantageous development of the invention it is provided that different micro channels have the same or different cross-sectional geometries along their respective axial directions. In other words it is provided that two or more micro channels have the same or different geometries. This also allows for a very precise definition of the flow behaviour of fluid(s) along the two or more micro channels.

A third aspect of the invention relates to a household appliance comprising at least one household appliance component, which is manufactured by a method according to the first aspect of the invention and/or configured according to the second aspect of the invention. The resulting features and their advantages can be gathered from the description of the first and the second aspect of the invention.

In a further advantageous development of the invention it is provided that the household appliance is configured as a hood, a washing machine, a dishwasher, or an induction, gas and/or radiant hob. Depending on the concrete design of the household appliance, this allows for precise dispensing of liquids, precise conduction of liquids, condensation of liquids within one or more micro channels, avoidance of water or liquid losses along the flow path, and reduction of raw material consumption for the generation of said micro channel(s). The micro channel(s) can for example be used as oil condensation channel(s) on hoods to guide oil to a reservoir, water condensation channel(s) on hoods to guide water to a reservoir, precise detergent channel(s) dispensation for washing machines, precise softener channel(s) dispensation for washing machines, water condensation channel(s) for dishwasher tubs, precise detergent channel(s) dispensation for dishwashers, or water or stain guiding channel(s) for induction, gas and radiant hobs.

Further features of the invention appear from the claims as well as based on the following embodiments. The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the embodiments are usable not only in the respectively specified combination, but also in other combinations without departing from the scope of the invention. There are thus also variations of the invention possible that are not explicitly shown and described in the embodiments but can, however, be formulated through different combinations of separated features from the described embodiments. Also variations and combinations of features are possible that do not contain all the features of an originally formulated independent claim.

In the following, embodiments of the invention are shown in more detail by referring to schematic drawings. These show in:

Fig. 1 a schematic drawing of a household appliance component according to the invention comprising a base element having a surface, wherein the base element comprises several micro channels for defining a flow path for fluids; and

Fig. 2 a schematic drawing of a household appliance component according to the invention comprising a base element with a coating, wherein the coating comprises several micro channels for defining flow paths for fluids. Fig. 1 shows a schematic drawing of a household appliance component 1. The household appliance component 1 comprises a base element 2 with a surface 3, wherein several micro channels 4 for defining a flow path for fluids are generated in the surface 3 of the base element 2. Each micro channel 4 has a uniform cross-sectional geometry along its respective axial direction. As can be seen from Fig. 1 , all micro channels 4 have individual cross- sectional geometries, namely a semicircular cross-sectional geometry, a triangular cross- sectional geometry, and a rectangular cross-sectional geometry. However, also uniform cross-sectional geometries are of course possible. The micro channels 4 may have a width (hydraulic diameter) of approximately 16 μηι, a height of approximately 2.4 μm, and a spacing of approximately 16 μηι. If the base element 2 is made from aluminum, spacings of between 10 μηι and 35 μηι, e.g. 30 μηι, between adjacent micro channels 4 have proven advantageous. Fig. 2 shows another schematic drawing of a household appliance component 1. In contrast to the previous embodiment, the household appliance component 1 comprises a base element 2 with a coating 5, wherein the coating 5 comprises several micro channels 4 for defining flow paths for fluids. The coating 5 can be selected from one or more of superhydrophobic coatings, superoleophobic coatings, and superhydrophilic coatings. It is also possible to use two or more coatings 5, wherein the coatings 5 may have the same or a different composition. The base element 2 can further be coated entirely or only in certain areas. It may further be provided that some micro channels 4 are generated in uncoated areas of the base element 2 while other micro channels 4 are generated in coated areas of the base element 2.

There are several applications for the household appliance components 1 , for example oil condensation channels on hoods to guide oil to a reservoir, water condensation channels on hoods to guide water to a reservoir, precise detergent channels dispensation for washing machines, precise softener channels dispensation for washing machines, water condensation channels for dishwasher tubs, precise detergent channels dispensation for dishwashers, or water or stain guiding channels for induction, gas and radiant hobs.

An example of a possible method for manufacturing micro channels 4 in a base element 2 made from stainless steel comprises the combined use of photolithography and ion milling. In a first step, a resin (for example photoresist AZ 6612 from MicroChemicals GmbH, Ulm, Germany) is applied to the surface 3 of the base element 2 (substrate) at 4000 rpm and baked at 110 °C for 50 s. Then UV light with a wave length of 405 nm is applied onto the resin with a power dose of between 125 and 175 mW/cm² passing through a mask with the desired channel pattern. In a following step, hard baking is performed at 125 °C during 2 min. Finally the household appliance component 1 is milled by ion milling for approximately 120 min at 500 V and 150 mA. Resin residues are removed with DMSO.

Another possibility for manufacturing micro channels 4 in a base element 2 and/or a coating 5 is the use of a UV laser, for example with 1 W power and 30 ns pulse time.

Important advantages of the household appliance component 1 comprise the precise dispensing of liquids, the precise conduction of liquids, the possibility to condense gases to liquids within micro channels 4, avoidance of water or liquid losses along the flow path, and the reduction of raw material consumption for the manufacturing of said micro channels 4.

It will be understood by those skilled in the art that while the present invention has been disclosed above with reference to preferred embodiments, various modifications, changes and additions can be made to the foregoing invention, without departing from the spirit and scope thereof. The parameter values used in the claims and the description for defining process and measurement conditions for the characterization of specific properties of the invention are also encompassed within the scope of deviations, for example due to measurement errors, system errors, weighing errors, DIN tolerances and the like.

LIST OF REFERENCE NUMERALS

1 household appliance component

2 base element

3 surface

4 micro channel

5 coating

Claims

1. A method for manufacturing a household appliance component (1), in which a base element (2) is provided, characterized in that at least one micro channel (4) for defining a flow path for fluids is generated in a surface (3) of the base element (2).

2. The method according to claim 1 , characterized in that a plurality of micro channels (4) is generated in the surface (3).

3. The method according to claim 1 or 2, characterized in that the at least one micro channel (4) is generated by at least one method selected from Nanoimprint Lithography (NIL), Micro-contact Printing (μCΡ), Step and Flash Imprint (SFIL), Roll-to-roll (R2R), Optical Lithography, Laser Lithography, Laser Interferometry, Extreme Ultraviolet Lithography (EUV), Focus Ion Beam Lithography (FIB), Ion Milling, and Electronic Beam Lithography (EBL).

4. The method according to any one of claims 1 to 3, characterized in that a base element (2) having a coating (5) is used and in that the at least one micro channel (4) is generated in the surface (3) of said coating (5).

5. The method according to claim 4, characterized in that the coating (5) is selected from one or more of superhydrophobic coatings, superoleophobic coatings, and superhydrophilic coatings.

6. A household appliance component (1), comprising a base element (2), characterized in that the base element (2) comprises at least one micro channel (4) for defining a flow path for fluids.

7. The household appliance component (1) according to claim 6, which is manufactured by a method according to any one of claims 1 to 5.

8. The household appliance component (1) according to claim 6 or 7, characterized in that the at least one micro channel (4) has a maximum hydraulic diameter of less than 1 mm, in particular of less than 500 μηι, and preferably of less than 50 μηι, and/or a maximum height of less than 100 μηι, in particular less than 50 μηι.

9. The household appliance component (1) according to claim 6 or 8, characterized in that at least two micro channels (4) are provided, wherein adjacent micro channels (4) are spaced between 5 μηι and 50 μηι from one another.

10. The household appliance component (1) according to any one of claims 6 to 9, characterized in that the at least one micro channel (4) has a uniform or non-uniform cross-sectional geometry along its axial direction.

1 1. The household appliance component (1) according to any one of claims 6 to 10, characterized in that the at least one micro channel (4) at least in sections has a semicircular or polygonal cross-sectional geometry.

12. The household appliance component (1) according to any one of claims 6 to 1 1 , characterized in that different micro channels (4) have the same or different cross- sectional geometries along their respective axial directions.

13. A household appliance comprising at least one household appliance component (1), which is manufactured by a method according to any one of claims 1 to 5 and/or configured according to any one of claims 6 to 12.

14. The household appliance of claim 13, which is configured as a hood, a washing machine, a dishwasher, or an induction, gas and/or radiant hob.