Household appliance with a sensor device

Abstract

Household appliance (1) with a sensor device (2), wherein the sensor device (2) is configured and designed to obtain information about the chemical and physical properties of a liquid based on the (spectral) measurement signature. For example, the turbidity of a liquid (7) can be determined using the measurement signature, wherein the sensor device (2) has a light transmitter side and a light receiver side, wherein light can be transmitted from the light transmitter side to the light receiver side and, after transmission, can be received by means of one or more light receivers (6), wherein the sensor device (2) is further configured and designed to detect the color of the liquid (7).

Description

The present invention relates to a household appliance having a sensor device, wherein the sensor device is designed and provided to obtain information about the chemical and physical properties of a liquid on the basis of the (spectral) measured value signature. Using the measured value signature, for example, the turbidity of a liquid can be determined. The liquid can be, for example, a process water or cleaning water and is arranged in a wet chamber of the household appliance. Turbidity arises, for example, due to optical scattering due to particles in the liquid and due to optical absorption of the individual constituents of the liquid. The household appliance can be, for example, a dishwasher, a washing machine or another device which can contain a liquid. The sensor device comprises a light transmitter side and a light receiver side, wherein light can be transmitted between the light transmitter side and the light receiver side and through the liquid which is at least partially arranged between the light transmitter side and the light receiver side. The light transmitted along the measurement path can be received at the end by means of one or more light receivers.Such household appliances with sensor devices are sufficiently known from the prior art, so that the turbidity of a corresponding liquid can be detected by means of this sensor device in order to be able to detect a degree of contamination of the cleaning water.According to the prior art, i.e. a domestic appliance with a sensor device for detecting turbidity of a cleaning water, however, it is not possible to draw conclusions as to the color of the cleaning water.Accordingly, the object of the present invention is to provide a household appliance with the sensor device, wherein the sensor device is provided and configured to detect a color of the cleaning water.This object is achieved by a household appliance having the features of claim 1 and by a method for determining a color of a liquid having the features of claim 20.The core idea of the present invention is to provide a household appliance with a sensor device, wherein the sensor device is designed and provided to detect turbidity of a liquid, for example a cleaning water. The sensor device comprises a light transmitter side and a light receiver side, wherein light can be transmitted from the light transmitter side to the light receiver side and can be received by means of a light receiver after the transmission. According to the invention, it is now provided that the sensor device is further provided and configured to detect a color of the cleaning water.Alternatively or cumulatively, it is conceivable that the optical absorption or transmission and / or the optical scattering by the liquid can be detected by means of the sensor device.Conclusions can be drawn on the composition of the medium on the basis of the color, since different sensor signals are to be expected depending on the composition. For example, the components of the liquid medium could be identified by color and determined both qualitatively and quantitatively. Components of the liquid medium could be, for example, various soils, detergents or dyes.Because the sensor device is now also designed to detect a color of the liquid, a corresponding reaction can be carried out when a discoloration of the liquid is detected. The sensor signals can be linked to a control unit, with which it is possible for the domestic appliance to be able to perform actions in a targeted manner as a function of the measurement results or to be able to control the operation of the domestic appliance.Such actions can be, for example, error messages, acoustic signals, adaptation of the washing program or communication with the smartphone via a wireless connection.For example, it is possible here that the laundry to be cleaned of a washing machine can be prevented by a person from being colored by the color in the liquid which has been released from textiles by way of example when said laundry receives a message to a mobile terminal.According to a particularly preferred embodiment, it can be provided that the sensor device has one or more light sources. Particularly preferably, the one or more light sources is arranged on the light transmitter side, i.e. on the light transmitter side. More preferably, at least two of the primary colors, i.e. red, green or blue, of the additive color mixture can be emitted by the one or more light sources by the one or more light sources. By attenuating the emitted light of the primary colors red, green or blue by the liquid, the corresponding color of the liquid can be determined. The light source can be formed from a plurality of individual light sources, which represent separate light sources. The light source can preferably be from the following group: an LED, a laser, a superluminescent LED, a thermal emitter, or any combination thereof, which can preferably emit at least two of the primary colors red, green and blue, optionally each with a specific wavelength. It is particularly preferably provided that the one or more light sources can emit three of the primary colors. Any color in the additive color space can be represented by the at least two, preferably three, of the primary colors.According to a particularly preferred embodiment, it is provided that at least two colors, more preferably three colors, of the visible light (390 nm to 790 nm) can be emitted or emitted by means of the one or more light sources. The colors are particularly preferably designed differently from one another in order to be able to cover the additive color space. Purely by way of example, the colour red having a peak wavelength from a range from 625 nm to 635 nm, the colour green having a peak wavelength from a range from 510 nm to 540 nm and the colour blue having a peak wavelength from a range from 450 nm to 480 nm can be emitted. Particularly preferred are the peak wavelengths for red at 630 nm, for green at 520 nm and for blue at 465 nm.According to a further preferred embodiment, it can be provided that at least one further light source is provided, that is to say one further or more further light sources. By means of the further light source(s), UV light and / or infrared (IR) light can be emitted. This makes it possible to gain additional information, such as scattering and the like on particles or fluorescence from the interaction of UV or IR light with the liquid.It is likewise conceivable to provide broadband light sources in the sensor device, such as LEDs which emit white light. If, for example, three colors are emitted by the light source or the light sources, then in the preferred embodiment peak wavelengths in the range 400-500 nm are conceivable for a first color, peak wavelengths in the range 500-600 nm for a second color, and peak wavelengths in the range 600-700 nm for a third color. The colors may span a color triangle in the color diagram. The spectrum of the light from the colored light sources in the visible region is typically subject to a Gaussian or Lorentz distribution around a peak wavelength. UV and IR light sources usually also have a Gaussian or Lorentz distribution around a peak wavelength.According to a preferred embodiment, it can be provided that the sensor device has a light guide. Light can be transmitted through a light guide in a simple and cost-effective manner. It can further preferably be provided that the light guide is divided into the light transmitter side and into the light receiver side. The light guide can accordingly make the light transmitter side and the light receiver side simple.Alternatively, it would be conceivable for the sensor device not to comprise a light guide, so that a direct emission of light from the light transmitter side to the light receiver side is provided.Particularly preferably, the light transmitter side and the light receiver side are arranged at a distance from one another. This means that the light source(s) and the light receiver / s are spaced apart from one another, wherein the distance is greater than zero.Further preferably, the one or more light sources is arranged on the light transmitter side. Preferably, the one or more light receivers are arranged on the light receiver side.The colors are emitted by the one or more light sources, transmitted by means of the light guide from the light transmitter side through the liquid to the light receiver side and transmitted accordingly to the light receiver. In order to avoid mixing with respect to the absorption rate when traversing the liquid, it is provided according to a particularly preferred embodiment that the colors can be emitted successively in a specific or determinable sequence by means of the light source(s). This means, for example, that first the first color, for example red, then the second color, for example green, and also finally the third color, for example blue, are emitted by the light source and corresponding signals are recorded.According to a further preferred embodiment, it is provided that after the light receiver emits a color, the light can be received and a corresponding sensor signal can be obtained.According to a preferred embodiment, it can be provided that different wavelength ranges can be received successively in a specific sequence by means of the one or more light receivers. As a result, the individual wavelengths can be evaluated or assigned one after the other.The sensor signal is particularly preferably dependent on the color of the liquid. Because the liquid is colored, for example, in a color that has colored out clothing, for example, the light of one color better is absorbed than the light of another color. Purely by way of example, blue and green light is more strongly absorbed when the liquid medium is colored red than the red light, which is only hardly absorbed here. For example, with an orange or yellow liquid, blue is absorbed most strongly, while green is little and red is hardly absorbed.The corresponding sensor signal of the light receiver is therefore dependent on the color of the cleaning water, so that conclusions can be drawn about the actual color.It is particularly preferably provided that the one or more light receivers is at least one selected from the group comprising a phototransistor, a photodiode, a bolometer, and any combination thereof. In principle, a laser diode would also be conceivable. With the aid of the light receiver, for example a phototransistor, the respective light can be detected and a corresponding signal can be output to the system. In a phototransistor, a photocurrent is generated by the received light, the greater the more light is received. The photocurrent can be tapped at the phototransistor by a suitable circuit and converted to another signal, for example a voltage. Similarly, an appropriate output signal is also generated for the other types of receivers. As further receivers, sensors or active layers lying one behind the other, for example phototransistors with different band gaps in the active zones, can be used. Moreover, 1-pixels or multi-pixel RGB cameras may serve as receivers.It is particularly preferred that phototransistors, photodiodes, bolometers, laser diodes or any combination of these mentioned receivers are used as light receivers. Along the measurement path, the light emitted by the transmitter is attenuated or attenuated and is detected at the end of the measurement path by the receiver, e.g. a phototransistor. The received light is then converted, for example, into an electrical signal, for example into a voltage. The value of the output signal is dependent on the attenuation of the light through the measurement path.Depending on which wavelength the emitted light has, it is attenuated to different extents along the measurement path by the media through which it passes. Thus, different output signals, for example in the form of an electrical voltage, are also to be expected for different wavelengths. On the basis of the resulting output signals, it is possible to infer the color of the liquid within the measurement path.It is further preferably provided that the sensor signal, for example a voltage for each color of the light received by the transmitter or the transmitters, is separately receivable at the light receiver or the light receivers, for example in the form of red, green, blue, for example. The corresponding or respective sensor signals can then be combined, for example by means of a control unit, in order to determine the color of the liquid, in the present case in the additive color space.Broadband receivers which can receive light in a large wavelength range can preferably be used. Furthermore, the receivers can be equipped, for example, with a short-pass or long-pass filter or a bandpass filter. The light sources could likewise be equipped with wavelength filters. However, these filters could also be realized as a separate component, for example on the transmitter side and / or the receiver side. The filters can also be arranged as a separate component in the form of a switchable, segmented filter wheel, so that different wavelength ranges are set for each segment, which can be filtered out. Such a filter wheel could be used on both the transmitter and receiver sides. A filter wheel could have different segments that filter out different wavelength ranges. Alternatively, the filters could be switchable glass, the transmission of which can be varied in certain wavelength ranges by applying an electrical voltage or a temperature. Such glasses may be electrochromic or thermochromic. It can also be an LC glass, the function of which is similar to an LC display. Furthermore, a plurality of receivers can also be arranged as a detector array.According to a particularly preferred embodiment, it is provided that the sensor device is calibrated or calibrateable. The calibration relates in particular to an unstained and clear or transparent liquid, i.e. for example tap water or distilled water. This has the result that, when the light is transmitted from the light transmitter side to the light receiver side or from light source(s) to light receiver(s), the sensor signal of the light receiver or the light receiver can be assigned to an unstained liquid, for example the cleaning liquid. By absorbing one or more light portions as a result of the discoloration of the liquid, the output signal of the sensor, for example the voltage which is output when the light is detected, also changes.The color in the additive color space can be represented and determined as follows.By the light or colors of the light, such as red, green, blue, being absorbed or partially absorbed by the liquid, the sensor output signal changes accordingly, which may be, for example, a voltage, a current, a PWM, or the like, and any combination thereof. This relationship applies to light of each wavelength, even in the applicable range between 200 nm and 2500 nm.It can be understood that the calibration is 100% or corresponds, so that an absorbed light color then makes up a correspondingly lower percentage. This percentage can be multiplied by the color factor of the additive color space of 255. The value 255 corresponds to the maximum value of the color for the respective color. If the percentage determined is multiplied by the color space value 255, a corresponding value in the additive color space arises for each of the colors present. The combination of the determined values in the color space for red, green and blue then specifies the three intensities in the additive color space, as a result of which the color in which the liquid is present can be determined.Alternatively, color space values may also be given on a scale as percentages with values of 0 to 100% and / or as a factor with values of 0 to 1 or in other units and, where appropriate, linear and nonlinear scalings thereof. The calculation of the color space values on the basis of the sensor signals is carried out each time analogously thereto.Furthermore, according to a particularly preferred embodiment, it is provided that in particular additionally an emission of an infrared light or a light in the infrared range is provided. This allows the turbidity of the present cleaning water to be checked, in particular assuming low optical absorption in the liquid in the IR spectrum. Because the intensity of the respective colors red, green, blue can likewise be reduced by reflections or scattering on dirt particles or the like in the case of a relatively turbid or high turbidity of the cleaning water, it is precisely provided that the colors be represented as a function of the turbidity of the cleaning liquid. It can thus be concluded whether absorption of a colour has occurred due to turbidity of the cleaning liquid or due to the colouring of the cleaning liquid.It is known that optical scattering can be wavelength dependent. Often shorter wavelengths are non-linearly more affected by the scattering than longer wavelengths. This applies globally both over the visible range and over the range of the broadened emission of the individual light sources. This nonlinearity changes the detected peak of emission and the light spectrum and shifts to longer wavelengths. This can be compensated for by a representative measurement of the scattering in the selected absorption-free IR range, for example based on software.Furthermore, it is possible that, according to a particularly preferred embodiment, it is provided that the cleaning liquid or the cleaning water is already precolored by a washing agent or the like. In order to recognize that the coloring of the cleaning water is due to the washing agent and not due to a color loss of clothing, for example, it may be possible to take into account the color tone of the washing agent in the present control unit. Changes in the color of the liquid which already has the color of the washing agent are also possible by means of the present invention.Furthermore, it can be provided that, according to a preferred embodiment, it is provided that the control unit can be sent to an application or the like, for example on a smartphone, by means of a notification when a discoloration or discoloration of the cleaning water, which is undesirable, is detected. As a result, the respective user of the domestic appliance can be informed that a coloring of the objects to be cleaned, for example the laundry, is to be expected and the washing process would therefore have to be discontinued.Accordingly, according to a further preferred embodiment, it can be provided that if a discoloration of the cleaning water is detected, the household appliance can be automatically stopped by a corresponding control signal of the control unit, so that a further discoloration of the object to be cleaned can likewise be avoided.Moreover, it is possible to provide a corresponding monitoring possibility with regard to different treatment processes by means of the coloring of the cleaning water, for example in the textile industry. Here, it would be advantageous that the waste water which is produced during the coloring process is introduced into the environment without the respective residue of the coloring agent.It is likewise conceivable according to a preferred embodiment that the calibration is not carried out with respect to an unstained and transparent water, but also, for example, with respect to a frequently used cleaning water with one or more specific detergent additives. This can be stored, for example, as a calibration, so that the influence of the washing agent can be kept low.According to a further preferred embodiment, it can be provided that the sensor device comprises a storage unit. For example, the various detergent additives, calibration settings, and the like can be stored in the storage unit and changed, added, or deleted as necessary. Accordingly, a corresponding set corresponding to the actual use of the household appliance can then be called up for each washing process.According to a further preferred embodiment, it can be provided that the sensor device is connected to a database, for example via the Internet / LAN and can communicate with it in both directions. For example, measured variables or determined characteristic variables, for example relating to various detergent additives, calibration settings and the like, can be stored in the database and changed, added or deleted as required. Accordingly, a corresponding set corresponding to the actual use of the household appliance can then be called up for each washing process. Furthermore, updates can be obtained via the database.According to a further preferred embodiment, it can be provided that the (spectral) measured value signature is evaluated with the aid of artificial intelligence (AI). The AI can assist in characterizing a liquid with respect to its chemical and physical properties.According to a further preferred embodiment, it is provided that exactly one light receiver is provided, for example in the form of a phototransistor. That is, the sensor device may comprise exactly one phototransistor. This makes it possible to further reduce the number of required components. Accordingly, the sensor device is therefore configured such that the different colors of the light source are redirected such that they can strike the phototransistor. For this purpose, the light deflection structure or a light guide element, for example a (totally reflecting) deflection mirror, is provided, which is designed such that the various light beams are concentrated on a surface that is as small as possible or are ideally or preferably focused at a point at which the phototransistor is located.According to a particularly preferred embodiment, the sensor device has a light guide element, wherein the light guide element is provided and configured to redirect light such that it is focused at a single point or near the single point. The light receiver is preferably arranged at this point.If, for example, a plurality of light sources are provided as separate components, the respective beam paths can be correspondingly combined and better detected by the light receiver.According to a further preferred embodiment, it can be provided that the light guide element is a parabolic element or is parabolic or is a curved surface. This allows the light to be deflected and focused into one point well.Further preferably, the light guide element is arranged on the light guide in the vicinity of the light receiver.According to a further preferred embodiment, it can be provided that the sensor device comprises a housing. Particularly preferably, the electronic components, such as light receiver, light source(s), light guides, are arranged within the housing. Further preferably, the housing is at least partially transparent. Further preferably, the housing is designed in such a way that it is sealed with respect to the liquid.The underlying object is likewise achieved by a method for determining a color of a liquid, wherein the method comprises the method steps: a) providing a household appliance according to a preferred embodiment; b) emitting light by means of the light source or a plurality of light sources; c) receiving the light by means of the light receiver or a plurality of light receivers and obtaining a sensor signal; d) combining the sensor signals and determining a color of the liquid.Further embodiments and embodiments of the embodiments with respect to one another can be applied to the further embodiments and can be freely combined with one another, provided they do not correspond to embodiments in the opposite direction. Further advantageous embodiments are evident from the dependent claims.The features with regard to the structural design and the method features can be used in a corresponding manner. Likewise, features which are disclosed merely in combination with further features can also be regarded as disclosed independently of these features.The invention is illustrated in more detail below in conjunction with the figures.Further objects, advantages and functionalities of the present invention can be gathered from the following description in conjunction with the figures and drawings. The following are shown here: FIG. 1 shows a household appliance with a sensor device; FIG. 2A shows a schematic illustration of the sensor device according to one embodiment; FIG. 2B shows a schematic illustration of the sensor device according to a further embodiment; FIG. 3 shows a circuit diagram of the sensor device according to one embodiment; FIG. 4 shows a wavelength spectrum; FIG. 5A is a photograph of samples; FIG. 5B Table of the samples; FIG. 6A shows a sensor device with a light guide element; FIG. 6B shows a sensor device with a light guide element; FIGS. 7A-7D show sensor devices according to the embodiments of FIGS. 6A and 6B FIG. 8 shows the method sequence for determining the color of the cleaning water.In the figures, identical components are to be understood in each case with the corresponding reference numerals. For clarity, some figures may not have components provided with a reference number, but have been designated elsewhere.According to FIG. 1, a household appliance 1 is schematically shown, which can be designed, for example, as a dishwasher, as a washing machine or the like. The household appliance 1 comprises a sensor device 2 which is integrated in the household appliance 1. In this case, it is preferably provided that the sensor device 2 is at least partially in contact with a liquid 7, for example a cleaning water 7. Likewise, a control unit 17 is shown, to which the sensor signals can preferably be linked. By means of the control unit 17, it may be possible for the household appliance 1 to be able to perform actions depending on the measurement results or sensor signals or to be able to control the operation of the household appliance 1. Such actions can be, for example, error messages, acoustic signals, adaptation of the washing program or communication with the smartphone via a wireless connection, such as WLAN, Bluetooth or the like.FIGS. 2A and 2B illustrate the sensor device 2 in more detail according to two embodiments, wherein certain components are already present, since the sensor device 2 is based on a turbidity sensor, so that additions with regard to the sensor device 2 now present are necessary. Regardless of the configuration, the sensor device 2 has a light transmitter side 3 and a light receiver side 4. At least one light source 5 and at least one light receiver 6 are likewise provided. Light can be emitted by means of the light source 5. For example, the light source 5 is an LED light source which can emit light with a specific wavelength or light with specific wavelengths.According to FIG. 2A, a section of the sensor device 2 is shown, wherein one or more light sources 5 are arranged on the light transmitter side 3 and one or more light receivers 6 are arranged on the light receiver side. Light can be emitted by means of the light source(s) 5 and received by means of the light receiver 6. By way of example, the light is illustrated as a light path L between light source 5 and light receiver 6.Further preferably, the light transmitter side 3 and the light receiver side 4 are arranged spaced apart from one another, that is to say are arranged at a distance 8 from one another. Particularly preferably, the sides 3, 4 are designed fingerlike. A liquid 7 is provided between the light transmitter side 3 and the light receiver side 4, so that the emitted light passes through the liquid 7 from the light transmitter side 3 to the light receiver side 4.Furthermore, a housing 14 is provided, in which the electronic components are located in order to seal them against the liquid 7.FIG. 2B shows a further or further embodiment of the sensor device 2.The sensor device 2 preferably comprises a light source 5 on the light transmitter side 3. Preferably, the first light guide element 12 is arranged on the light transmitter side 3 and the second light guide element 13 is arranged on the light receiver side 4. The light guide elements 12, 13 can preferably be connected to one another, for example by means of a connecting element 15. The explanations and embodiments of FIG. 2A also apply to FIG. 2B.The light, represented by the light path L, of the light source 5 is emitted to the first light guide element 12, transported by means of the first light guide element 12 and transmitted to a second light guide element 13. In this case, it is particularly preferably provided that the light guide elements 12, 13 are spaced apart from one another at a distance 8. When the light is guided in the second light guide element 4, the light is transmitted to one or more light receivers 6, wherein the light receiver 6 is designed in such a way as to receive the light and output a corresponding sensor signal. When transmitting the light from the first light guide member 12 to the second light guide member 13, the light passes through the liquid 7.Because the light guides 12, 13 can already be present, the light source 5 and the light receiver 6 are arranged at a distance from the respective light guide elements 12, 13. In turbidity sensors already present, the existing standard turbidity sensor design can be used, for example, by providing a multichip LED, which can emit the colors red, green and blue and / or white, for example. Thus, the functionality with regard to the detection of one of the colors of the liquid 7 can be integrated subsequently into the turbidity sensor already present.It can also be provided that the light receiver 6 and the light source 5 can be connected to one another at least in terms of signal technology, so that a change or deviation of the received sensor signal of the light receiver 6 is compared depending on the reference value present in the light source 5.Particularly preferably, the light arriving at the light receiver 6 is converted into an electrical variable, for example a voltage, by means of a suitable circuit, wherein the electrical variable, that is to say for example the voltage, can represent the output signal. If a reference liquid is present between the light sides 3, 4 during the measurement, the output signal, for example a voltage, can be taken as a reference value for the reference state. Any deviation from the reference state generates a different measurement result or a different output signal, such as a voltage. On the basis of the absorption or attenuation of light or certain wavelengths of the light, it is then possible to draw conclusions as to the color of the liquid 7.The sensor signal is dependent on the intensity or a non-absorbed part of the transmitted light.It is particularly preferred that the light receiver 6 is designed as a phototransistor. The phototransistor is sensitive to the transmitted light, and when light impinges on the phototransistor, the photoelectric effect generates a photocurrent which can be further processed to form an output signal using a suitable electrical circuit. The output signal may be, for example, a voltage which is consequently dependent on the intensity of the light arriving at the receiver.An exemplary section of the interconnection of the present light source 5 and the light receiver 6 is present according to FIG. 3. Likewise, one or more further light sources 16 can be provided, which can emit UV light and / or IR light, for example. In principle, depending on the configuration of the sensor device 2, the circuit can be adapted accordingly.The sensor device 2 can preferably be calibrated accordingly, wherein calibration can be carried out, for example, with respect to a reference liquid. Particularly preferably, the reference liquid can be clear water or distilled water, so that the received light can be indicated as the reference by means of the light receiver 6 and the corresponding sensor signal. If the emitted light is attenuated along the measurement path, the output signal changes as a function of this attenuation. By means of the deviation from the reference signal, conclusions can be obtained about the properties of the liquid, such as the color.According to FIG. 4, it is shown by way of example which colors can be emitted by means of the one or more light sources 5. In this case, it is provided, as also shown in FIG. 3, that the light source 5 is provided to emit at least three different colors, wherein the emitted colors are more preferably primary colors red, green and blue of the additive color mixture. According to FIG. 4, it is further provided where the respective wavelength ranges or the corresponding peak wavelength of the respective range can lie.FIGS. 5A and 5B show a series of samples with the corresponding evaluation and how the color of the liquid 7 can be determined by the sensor device 2.The present system with the sensor device 2 is calibrated or referenced to distilled water. Further samples are given here, which are numbered or designated accordingly. The color differences can be clearly seen in FIG. 5A. The values output by the light receiver 6 with regard to the transmitted colors red, green and blue are accordingly stored as 100%. Deviations in the output of the light receiver 6, i.e. of the phototransistor, are accordingly given in lower percentages. This can be seen, for example, in the case of samples D 3 and D 2. It is also possible to see which of the colors red, green and blue are absorbed accordingly.After determination or after obtaining the respective sensor values, these values are multiplied by the maximum value of the additive color space, this value being 255. The value obtained, i.e. the multiplied value of the 255 value times the respective percentage, yields the respective value in the additive color space. This is carried out with each of the colors red, green, blue, so that the respective color tone of the additive color space can be determined by the combination of the three multiplication values. As can be seen from the comparison of the colors of Figs. 5A and 5B, the calculation is very accurate.In section A of FIG. 5B, the respective measurement values and the reference value are shown. In section B of FIG. 5B, the ratio of the respective measured value to the reference value is shown. In section C, the respective calculated value of the additive color space is finally shown, by means of which the color in the additive color space can be determined.According to a preferred embodiment, it should be provided that a single light receiver 6 is provided. In order to be able to focus different light beams or a plurality of light paths onto the single light receiver element 6, it is preferably provided that a light guide element 9 is provided, wherein the light guide element 9 is provided and configured to deflect light in such a way that it is focused into a single point. This light guide element 9 is particularly preferably illustrated in FIG. 6A, wherein light guide element 9 is a parabolic element or curved surface 10. The designations LED 1 to LED 4 are shown here for different outputs or light emissions of the light source 5, which can correspond, for example, to the colors red, green, blue and an infrared light source.Conversely, according to one embodiment, as shown in FIG. 6B, it would be possible for a single light source 5 to be provided, which is provided, for example, as a broadband light source, for example a white-colored LED, which can be divided by means of the light guide element 9 or the parabolic element 10, which can emit the respective light signal to phototransistors formed accordingly, wherein the phototransistors are preferably formed such that they are sensitive only with respect to a specific wavelength range or filters corresponding to the light guide element 9 and the phototransistor are arranged, which can filter the light of the light source 5. The filters can preferably also be arranged in the respective light receiver.Purely by way of example, a sensor device 2 with the light guide element 10 is illustrated in FIGS. 7A to 7D. FIGS. 7A and 7B show a plurality of light sources 5 in the case of a single light receiver 6. FIGS. 7C and 7D show a plurality of light receivers 6 in the case of a single light source 5.According to FIGS. 7A and 7B, at least two light sources 5, 5', 5" are shown, which are each assigned to a first or second light path L', L". The transmission of the light from the light source 5, 5', 5" to the light receiver 6 has already been illustrated. In front of the light receiver 6, the light guide element 9 is now additionally arranged, which focuses the light paths L', L" onto a point in which the light receiver 6 is arranged.FIGS. 7C and 7D show the different type of case, with a single light source 5 and a plurality of light receivers 6, 6', 6".FIG. 8 shows, purely by way of example, the method for determining a color of the cleaning water 7, wherein the method comprises the method steps:S 1: in this step, a corresponding household appliance 1 is provided, which has the sensor device 2 according to the invention. In the next step S 2, light is emitted by means of the light source 5 and is preferably transmitted via the light guides 3, 4 to the light receiver 6. In step S 3, the light is received by means of the light receiver 6 and a corresponding sensor signal of the light receiver 6 is obtained. After receiving the respective sensor signal, for example for the different colors of the light source 5, these sensor signals are combined with one another and the color of the cleaning water 7 is determined from the combination of the sensor signals.The applicant reserves the right to claim all the features disclosed in the application documents as essential to the invention, provided they are novel, individually or in combination, compared with the prior art. It is also pointed out that features have also been described in the individual figures, which features may be advantageous per se. The skilled person directly recognizes that a specific feature described in a figure can also be advantageous without the adoption of further features from this figure. Furthermore, the skilled person recognizes that advantages can also result from a combination of a plurality of features shown in individual figures or in different figures.List of reference characters1 Household appliance 2 Sensor device 3 Light transmitter side 4 Light receiver side 5. 5', 5" Light source 6, 6', 6" Light receiver 7 Liquid, cleaning water 8 Distance 9 Light guide element 10 Parabolic element 11 Light guide 12 First light guide element 13 Second light guide element 14 Housing 15 Connecting element 16 Further light source 17 Control unit L, L', L" Light path

Claims

Domestic appliance (1) with a sensor device (2), wherein the sensor device (2) is designed and provided for this purpose, wherein information about chemical and / or physical properties of a liquid, for example turbidity of a liquid (7), can be determined on the basis of a spectral measured value signature, wherein the sensor device (2) has a light transmitter side and a light receiver side, wherein light can be transmitted from the light transmitter side to the light receiver side and can be received after the transmission by means of one or more light receivers (6), characterised in that the sensor device (2) is further provided and designed to detect a colour of the liquid (7).Domestic appliance (1) according to claim 1, characterised in that the sensor device (2) has one or more light sources (5) on the light transmitter side, wherein at least two of the primary colours of the additive colour mixture can be emitted by the one or more light sources (5).Household appliance (1) according to claim 2, characterised in that the one or more light sources can emit three of the primary colours.Domestic appliance (1) according to claim 1, characterised in that the sensor device has one or more light sources, by means of which a broadband spectrum can be emitted.Domestic appliance (1) according to one of claims 1 to 4, characterised in that at least one further light source is provided, by means of which infrared and / or UV light can be emitted.Household appliance according to claim 5, characterised in that the at least one further light source is one selected from the group comprising: an LED, a laser, a superluminescent LED, or any combination thereof.Household appliance (1) according to one of claims 2 to 3, characterised in that the colours can be emitted successively in a specific sequence by means of the one or more light sources (5).Domestic appliance according to one of claims 1 to 7, characterised in that different wavelength ranges can be received successively in a specific sequence by means of the one or more light receivers.Household appliance (1) according to one of claims 2 to 7, characterised in that after the emission of a colour the light can be received by means of the one or more light receivers (6) and a corresponding sensor signal can be obtained, wherein the sensor signal is dependent on the colour of the liquid (7).Household appliance (1) according to claim 9, characterised in that the one or more light receivers (6) is at least one selected from the group comprising a phototransistor, a photodiode, a laser diode, a bolometer, and any combinations thereof, such that the sensor signal is at least one selected from the group comprising a voltage, a current, PWM, or any combination thereof, wherein the sensor signal is receivable for each colour and the respective sensor signals are combinatable in order to determine the colour of the liquid (7) in the additive colour space.Household appliance according to one of claims 1 to 10, characterised in that the sensor device comprises a light guide which is divided into the light transmitter side and into the light receiver side.Household appliance according to claim 11, characterised in that the light guide comprises a first light guide element and a second light guide element, wherein the light transmitter side is provided by the first light guide element and the light receiver side by the second light guide element.Household appliance according to one of claims 1 to 12, characterised in that the light transmitter side and the light receiver side are arranged at a distance from one another.Domestic appliance according to claim 11 or 12, characterised in that the light guide has a light guide element, wherein the light guide element is provided and configured to deflect light in such a way that it is focused into a single point, wherein a single light receiver is provided in the single point.Household appliance according to claim 14, characterised in that the light guide element is a parabolic element and / or a curved surface.Domestic appliance according to one of claims 1 to 13, characterised in that the light guide has a light guide element, wherein the light guide element is provided and configured to split light with a broadband spectrum into a plurality of individual light beams.Domestic appliance according to claim 16, characterised in that a plurality of light receivers are provided, which are provided and configured to receive the individual light beams.Domestic appliance according to claim 16, characterised in that a single light receiver is provided, which is provided and designed to receive broadband light.Household appliance according to claim 17, characterised in that the light receivers each have a different spectral sensitivity, so that each of the light receivers can receive light with a different colour.Domestic appliance according to claim 17, characterised in that one or more optical filter elements are arranged between the light receiver and the light guide element, which are provided and configured to optically filter the light.Household appliance according to one of the preceding claims, characterised in that the spectral measurement value signature can be evaluated with the aid of artificial intelligence (Kl), in particular with regard to the characterisation of a liquid in its chemical and physical properties.Method for determining a colour of a cleaning water (), comprising the method steps: a) providing a household appliance (1) according to one of claims 1 to 19; b) emitting light by means of the light source (5); c) receiving the light by means of the one or more light receivers (6) and obtaining a sensor signal; d) combining the sensor signals and determining a colour of the liquid (7).

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