DE102011079488A1 - Method and device for detecting a water change in a water-conducting household appliance, in particular a dishwasher - Google Patents

Abstract

Method for detecting a water change in a water-conducting domestic appliance, in particular a dishwasher, comprising a sensor for detecting water, a sensor for detecting the temperature, a control unit for processing the sensor data, the method comprising the following steps (a) detection of water in one 1 after at least two, preferably at least three consecutive measuring points within a time interval ZIw, 1 the absence of water was detected, the method step (b.) is carried out, (b.) detection of water in a defined time interval ZIw, 2 wherein after at least one determination of the presence of water within the time interval ZIw, 2 the process step (c.) Is carried out, (c.) Detection of the temperature in a time interval ZIT, 3 wherein the process step (d.) Is carried out if at at least two, preferably at least three aufe in the following within the time interval ZIT, 3 lying temperature measuring intervals ZIT, 4 the temperature T1 at the beginning of the measuring interval ZIT, 3 is greater than the temperature T2 at the end of the measuring interval ZIT, 3, (d.) performing the method step (e between the detection of water according to method step (b.) and the at least three successive detection of a negative temperature gradient according to method step (c.) Less than two minutes, (e.) Generation of a control signal by the control unit due to a detected water change according to the method steps (a.) to (d.).

Description

The invention relates to a method and a device for detecting a water change in a water-conducting household appliance, in particular a dishwasher.

State of the art

Automatic, self-sufficient by a dishwasher dosing devices which deliver a plurality of mutually different preparations with a time delay in the rinsing process, are known in the prior art.

Such metering devices work relatively reliably, as long as they are operated within typical and static washing programs.

In the field of programs for dishwashers, however, so-called automatic programs have been established, which can dynamically adapt or change their program sequence within an automatic program on the basis of supplied sensor data, such as from a turbidity sensor, and so according to the machine load and existing pollution load an energy to deliver water-efficient and / or rinsing-result-optimized results without the user having to intervene.

With the above-mentioned metering devices, it is currently possible to reliably detect the beginning of a wash program, even of automatic programs, but these dispensers encounter when dispensing preparations in particular in the final rinse section of a wash program at borders, because due to the dynamic Spülprogrammanpassung the automatic programs, for example a metering of a final rinse phase after a defined time after detection of the start of the wash cycle can lead to a delivery before the start of the final rinse section in an automatic program. Since, in such a case, the rinse aid preparation is not available in the final-rinse program, since a water rinse usually occurs before a rinse-aid section within a rinse program, the resulting rinse result is generally not optimal.

The object of the invention is therefore to provide a method and a device with which a water change, in particular before a final rinse section within a washing program, can be detected.

This object is achieved by a method according to claim 1 and a device according to claim X.

• (a.) Detektion von Wasser in einem definierten Zeitintervall ZI_w,1 von 2–120 sec, bevorzugt 5–60 sec, besonders bevorzugt 10–30 sec wobei nach wenigstens zwei, bevorzugt wenigstens drei aufeinander folgenden Messpunkten innerhalb eines Zeitintervalls ZI_w,1das Nichtvorhandensein von Wasser detektiert wurde der Verfahrensschritt (b.) ausgeführt wird,
• (b.) Detektion von Wasser in einem definierten Zeitintervall ZI_w,2 von 1 ms–120 sec, bevorzugt 5ms–60 sec, besonders bevorzugt 10ms–30 sec wobei nach (wenigstens) einmaligem Feststellen des Vorhandenseins von Wasser innerhalb des Zeitintervalls ZI_w,2 der Verfahrensschritt (c.) ausgeführt wird,
• (c.) Detektion der Temperatur in einem Zeitintervall ZI_T,3 von 2–120 sec, bevorzugt 5–60 sec, besonders bevorzugt 10–30 sec wobei der Verfahrensschritt (d.) ausgeführt wird, wenn bei wenigstens zwei, bevorzugt wenigstens drei aufeinander folgenden innerhalb des Zeitintervall ZI_T,3 liegenden Temperatur-Messintervallen ZI_T,4 die Temperatur T₁ zu Beginn des Messintervalls ZI_T,3 größer ist als die Temperatur T₂ am Ende des Messintervalls ZI_T,3,
• (d.) Ausführen des Verfahrensschritts (e.), wenn zwischen der Detektion von Wasser gemäß Verfahrensschritt (b.) und der wenigstens dreimal aufeinander folgenden Detektion eines negativen Temperaturgradienten gemäß Verfahrensschritt (c.) weniger als zwei Minuten liegen,
• (e.) Erzeugung eines Steuersignals durch die Steuereinheit aufgrund eines detektierten Wasserwechsels gemäß den Verfahrensschritten (a.) bis (d.).

The inventive method for detecting a water change in a water-conducting household appliance, in particular a dishwasher, comprises a sensor for detecting water, a sensor for detecting the temperature and a control unit for processing the sensor data, wherein the method comprises the following steps

• (a.) detection of water in a defined time interval ZI _{w, 1} of 2-120 sec, preferably 5-60 sec, more preferably 10-30 sec wherein after at least two, preferably at least three consecutive measurement points within a time interval ZI _{w, 1} the absence of water has been detected, the process step (b.) Is carried out,
• (b.) Detection of water in a defined time interval ZI _{w, 2} of 1 ms-120 sec, preferably 5ms-60 sec, more preferably 10ms-30 sec wherein after (at least) once detecting the presence of water within the time interval ZI _{w 2,} the method step (c.) Is carried out,
• (c.) Detection of the temperature in a time interval ZI _{T, 3} of 2-120 sec, preferably 5-60 sec, more preferably 10-30 sec wherein the process step (d.) Is carried out when at least two, preferably at least three successive within the time interval ZI _{T, 3} lying temperature measuring intervals ZI _{T, 4} the temperature T ₁ at the beginning of the measuring interval ZI _{T, 3 is} greater than the temperature T ₂ at the end of the measuring interval ZI _{T, 3} ,
• (d.) carrying out the method step (e.) if less than two minutes lie between the detection of water according to method step (b.) and the at least three successive detection of a negative temperature gradient according to method step (c.),
• (e.) generating a control signal by the control unit due to a detected water change according to the method steps (a.) to (d.).

It is particularly preferred that the control signal causes the dosing of a rinse aid preparation into the interior of a dishwasher after a detected water change. This ensures, in particular, that at the end of an automatic program, a rinse aid preparation is metered into the final-rinse program section.

In a particularly preferred embodiment of the method according to the invention, the method with the method steps (a.) - (e.) Is carried out only after at least a first dishwashing detergent preparation, preferably an enzyme-containing dishwashing detergent preparation, was released into the interior of the dishwasher, wherein the release of at least first dishwashing detergent preparation takes place if at least one temperature> 25 °, preferably> 29 ° C and the presence of water was detected. A detailed description of the detection of the beginning of a rinse program has been provided by the Applicant in DE 10 2010 002 750.2 discloses, wherein DE 10 2010 002 750.2 is incorporated by referencing in the disclosure of the present application. Thus, it is thus particularly advantageous to carry out the method according to the invention only after at least one detergent preparation has already been dispensed at the beginning of the rinsing process.

It is particularly advantageous in this connection that the preparations which are metered into the rinsing process are different from one another, it being especially advantageous that the preparations dosed at the beginning of the rinsing process and the preparations added after the detection of a water change are different from each other.

In a further preferred embodiment of the invention, the method with the method steps (a.) - (e.) Is carried out after after the release of the first dishwashing detergent preparation at least a second dishwashing detergent preparation, preferably an alkaline dishwashing detergent preparation, was released into the interior of the dishwasher.

The present invention further relates to a device for dosing a rinse aid preparation in the interior of a dishwasher comprising a sensor for detecting water, a sensor for detecting the temperature, a control unit for processing the sensor data, wherein the control unit is configured to carry out the method according to the invention.

The metering device is preferably freely positionable by a user in the interior of a dishwasher. Furthermore, it is advantageous that the device comprises a cartridge with at least one chamber in which at least one rinse aid preparation is stored.

metering

The metering device comprises a metering device with a detachable or non-detachably coupled to the metering cartridge, which has at least one chamber with a dishwashing detergent preparation. In particular, the control unit necessary for carrying out the method according to the invention and at least one sensor for detecting water and a sensor for detecting the temperature are integrated in the dosing device. Preferably, an actuator for releasing a dishwashing detergent preparation and / or an energy source are also arranged on or in the dosing device.

sensors

The metering device preferably has at least one sensor for detecting water and a sensor for detecting the temperature. The temperature sensor is designed in particular for detecting a water temperature.

It is further preferred that the metering device comprises a sensor for detecting the conductivity, whereby in particular the presence of water or the spraying of water, in particular in a dishwasher, is detected.

In an advantageous embodiment of the invention, the sensor unit comprises at least one, at least 2-pole conductivity sensor. Preferably, at least two poles of the conductivity sensor have a distance of 2-25 mm, preferably 5-15 mm, particularly preferably about 12 mm.

To be particularly advantageous has been found that at least two poles of a conductivity sensor are coated with an electrically conductive silicone, in particular, it is preferable that a in the Substantially planar surface is formed between the silicone and an outer dosing device surface. Due to the elastomeric properties of the conductive silicone, the sensor can be sealed in a simple and effective manner with respect to the environment and embedded in a housing wall of the dosing device.

In order to maintain the measurement accuracy over a large number of measurements, it is advantageous that, after each resistance measurement, a polarity reversal occurs at the 2-pole conductivity sensor, so that no charge excesses can form on the conductivity sensor.

It is particularly preferred that at least two sensor units are provided for measuring mutually different parameters, wherein very particularly preferably a sensor unit is a conductivity sensor and a further sensor unit is a temperature sensor.

The sensors are especially adapted to detect the beginning, the course and the end of a washing program. For this purpose, by way of example and not limitation, the sensor combinations listed in the following table can be used Sensor 1 Sensor 2 Sensor 3 Sensor 4 conductivity sensor temperature sensor conductivity sensor temperature sensor brightness sensor conductivity sensor temperature sensor brightness sensor turbidity sensor

By means of the conductivity sensor can be detected, for example, whether the conductivity sensor is wetted by water, so that, for example. determine if there is water in the dishwasher.

The conductance or conductivity sensor may consist of an electrically conductive anode and a cathode which protrude from the housing of the metering device into the interior of the dishwasher or are electrically conductively connected to the interior of the dishwasher. Preferably, the distance of the anode and cathode is selected so that an electrically conductive water bridge between the anode and cathode can form during operation of the dishwasher, which can be measured by a drop in the resistance between the anode and cathode.

Rinsing programs usually have a characteristic temperature profile, the u.a. is determined by the heating of the rinse water and the drying of the dishes, which can be detected by a temperature sensor.

However, in order to enable efficient production and assembly of the dosing device, it is also possible for at least one sensor unit to be arranged on or in the control unit. For example, it is possible to provide a temperature sensor in the dosing device or directly on the board carrying the control unit, so that the temperature sensor has no direct contact with the surroundings.

control unit

A control unit in the sense of this application is a device which is suitable for influencing the transport of material, energy and / or information. For this purpose, the control unit influences actuators by means of control signals with the aid of information, in particular of measuring signals of the sensor unit, which processes them in the sense of the control target.

In particular, the control unit may be a programmable microprocessor. In a particularly preferred embodiment of the invention, a plurality of dosing programs are stored on the microprocessor.

The control unit has, in a preferred embodiment, no connection to the possibly existing control of the household appliance. Accordingly, no information, in particular electrical, optical or electromagnetic signals, is exchanged directly between the control unit and the control of the household appliance.

In an alternative embodiment of the invention, the control unit is coupled to the existing control of the household appliance. Preferably, this coupling is wireless. For example, it is possible to position a transmitter on or in a dishwasher, preferably on or at the dosing chamber embedded in the door of the dishwasher, which wirelessly transmits a signal to the dosing device when the control of the domestic appliance controls the dosage of, for example, a detergent from the dosing device Dosing or rinse aid causes. Thus, it is possible that the controller of the dishwasher sends control signals to the metering device for dispensing certain preparations and Dosiermengen.

It is also conceivable that when it comes to interfacing with the control of the dosing device in the coupling of the control of the dishwasher, for example, to a signal break in the wireless signal transmission, this signal separation is detected by the control of the dosing and switched back to an internal dosing program, so that despite disturbance in the signal transmission, the dosage of preparation from the metering device is ensured in the flushing process. A corresponding procedure was developed by the applicant in DE 10 2009 009 194.7 This application is incorporated by referencing in the disclosure of this application.

The delivery of preparations from the dosing device can be done sequentially or simultaneously.

It is particularly preferred to dose a plurality of preparations sequentially in a rinsing program. In particular, the following metering sequences are to be preferred 1st dosage 2nd dosage 3. Dosage 4. Dosage Enzymatic cleaning preparation Alkaline cleaning preparation Alkaline cleaning preparation rinse aid Enzymatic cleaning preparation Alkaline cleaning preparation rinse aid Enzymatic cleaning preparation Alkaline cleaning preparation rinse aid disinfecting preparation Enzymatic cleaning preparation Alkaline cleaning preparation rinse aid perfume pretreatment preparation Enzymatic cleaning preparation Alkaline cleaning preparation rinse aid

Furthermore, it is advantageous that at least one enzyme-containing preparation and / or alkaline preparation is released in the pre- and / or main wash program of the dishwasher, the release of the enzyme-containing preparation preferably taking place before the release of the alkaline preparation. Furthermore, it is preferred that the dosing of the rinse aid takes place in the rinse aid program of the dishwasher, wherein the rinse aid program is recognized by a water change according to the inventive method described here.

According to a further preferred embodiment of the invention, a discontinuous, discrete resistance measurement takes place on the conductivity sensor and preferably also on the temperature sensor. Due to the discontinuous, discrete measurement in particular the electrical energy consumption of the control unit is reduced.

The invention will be explained in more detail with reference to the listed figures. Show it

1 Dosing device in dishwasher

2 Flow chart of the water change detection

1 shows a metering device consisting of a positionable metering device 2 with a two-chamber cartridge 1 in the dish drawer 11 with the dishwasher door open 39 a dishwasher 38 , In the dosing device 2 a control unit, a temperature sensor and a conductivity sensor are arranged. It can be seen that the dosing device 2 with the cartouche 1 in principle at any point inside the dish drawer 11 can be positioned, it is advantageous, a dish-shaped or cup-shaped dosing 1 . 2 in a corresponding plate or cup holder of the dish drawer 11 provided.

In the dishwasher door 39 there is a dosing chamber 53 into which a dishwasher cleaner preparation may be added, for example in the form of a tablet. An advantage of this embodiment of the invention is that with the arrangement of the positionable dosing system 1 . 2 in the lower or upper (not shown) dish drawer 11 the delivery of the preparations 40a . 40b from the cartouche 1 takes place directly over the bottom of the dispenser arranged outlet openings in the rinse water liquor, so that a quick solution and uniform distribution of the rinse in the wash program is guaranteed. Furthermore, this ensures that the conductivity sensor, which is arranged in the shown operating position of the dosing device in the direction of gravity at the bottom of the dosing device, during operation of the dishwasher direct spraying of the conductivity sensor with rinse water is effected by a spray arm and the control unit and the conductivity sensor are configured such a discontinuous, discrete resistance measurement is carried out on the conductivity sensor and preferably also on the temperature sensor.

• (a.) Detektion von Wasser in einem definierten Zeitintervall ZI_w,1 von 2–120 sec, bevorzugt 5–60 sec, besonders bevorzugt 10–30 sec wobei nach drei aufeinander folgenden Messpunkten innerhalb eines Zeitintervalls ZI_w,1 das Nichtvorhandensein von Wasser detektiert wurde der Verfahrensschritt (b.) ausgeführt wird,
• (b.) Detektion von Wasser in einem definierten Zeitintervall ZI_w,2 von 1 ms–120 sec, bevorzugt 5ms–60 sec, besonders bevorzugt 10ms–30 sec wobei nach einmaligem Feststellen des Vorhandenseins von Wasser innerhalb des Zeitintervalls ZI_w,2 der Verfahrensschritt (c.) ausgeführt wird,
• (c.) Detektion der Temperatur in einem Zeitintervall ZI_T,3 von 2–120 sec, bevorzugt 5–60 sec, besonders bevorzugt 10–30 sec wobei der Verfahrensschritt (d.) ausgeführt wird, wenn bei drei aufeinander folgenden innerhalb des Zeitintervall ZI_T,3 liegenden Temperatur-Messintervallen ZI_T,4 die Temperatur T₁ zu Beginn des Messintervalls ZI_T,3 größer ist als die Temperatur T₂ am Ende des Messintervalls ZI_T,3. Die Temperaturmesswerte T₁ und T₂ werden hierzu jeweils in einen internen Speicher der Steuereinheit geschrieben, ebenso wie die Zeitmesswerte t_b zu Beginn des Verfahrenschritts (c.) und t_c zum Ende des Verfahrensschritts (c.)
• (d.) Ausführen des Verfahrensschritts (e.), wenn zwischen der Detektion von Wasser gemäß Verfahrensschritt (b.) und der wenigstens dreimal aufeinander folgenden Detektion eines negativen Temperaturgradienten gemäß Verfahrensschritt (c.) weniger als zwei Minuten liegen, wenn also die Bedingung t_c–t_b < 2min erfüllt ist
• (e.) Erzeugung eines Steuersignals durch die Steuereinheit aufgrund eines detektierten Wasserwechsels gemäß den Verfahrensschritten (a.) bis (d.).

The 2 shows an embodiment of the method according to the invention in the form of a flow chart, wherein the method comprises the following steps

• (a.) Detection of water in a defined time interval ZI _{w, 1} of 2-120 sec, preferably 5-60 sec, more preferably 10-30 sec wherein after three consecutive measurement points within a time interval ZI _{w, 1} the absence of water was detected, the process step (b.) Is carried out
• (b.) Detection of water in a defined time interval ZI _{w, 2} of 1 ms-120 sec, preferably 5ms-60 sec, more preferably 10ms-30 sec wherein after a single detection of the presence of water within the time interval ZI _{w, 2} the Process step (c.) Is carried out,
• (c.) Detection of the temperature in a time interval ZI _{T, 3} of 2-120 sec, preferably 5-60 sec, more preferably 10-30 sec wherein the process step (d.) Is carried out when three consecutive within the time interval ZI _{T, 3} lying temperature measuring intervals ZI _{T, 4} the temperature T ₁ at the beginning of the measuring interval ZI _{T, 3 is} greater than the temperature T ₂ at the end of the measuring interval ZI _{T, 3} . For this purpose, the temperature measured values T ₁ and T ₂ are respectively written into an internal memory of the control unit, as are the time measured values t _b at the beginning of the method step (c.) And t _c at the end of the method step (c.).
• (d.) carrying out the method step (e.) If less than two minutes lie between the detection of water according to method step (b.) and the at least three successive detection of a negative temperature gradient according to method step (c.), that is, if the condition t _c -t _b <2min is met
• (e.) generating a control signal by the control unit due to a detected water change according to the method steps (a.) to (d.).

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102010002750 [0010, 0010]
• DE 102009009194 [0031]

Claims (9)

Method for detecting a water change in a water-conducting domestic appliance, in particular a dishwasher, comprising • a sensor for detecting water • a sensor for detecting the temperature • a control unit for processing the sensor data, the method comprising the following steps (a.) Detection of water in a defined time interval ZI _{w, 1} of 2-120 sec, preferably 5-60 sec, more preferably 10-30 sec wherein after at least two, preferably at least three consecutive measuring points within a time interval ZI _{w, 1} the absence of water was detected the method step (b.) is carried out, (b.) detection of water in a defined time interval ZI _{w, 2} of 1 ms-120 sec, preferably 5ms-60 sec, more preferably 10ms-30 sec wherein after at least one detection of the presence of water within the time interval ZI _{w, 2} the process step (c.) is carried out, (c .) Detection of the temperature in a time interval ZI _{T, 3} of 2-120 sec, preferably 5-60 sec, more preferably 10-30 sec wherein the process step (d.) Is carried out if at least two, preferably at least three consecutive within the time interval ZI _{T, 3} lying temperature measuring intervals ZI _{T, 4} the temperature T ₁ at the beginning of the measuring interval ZI _{T, 3 is} greater than the temperature T ₂ at the end of the measuring interval ZI _{T, 3} , (d.) Performing the method step (e.) if there is less than two minutes between the detection of water according to method step (b.) and the at least three successive detection of a negative temperature gradient according to method step (c.), (e.) generation of a control signal by the control unit a detected water change according to the process steps (a.) to (d.). Method according to one of the preceding claims, characterized in that the control signal causes after a detected water change, the dosage of a rinse aid preparation in the interior of a dishwasher. Method according to one of the preceding claims, characterized in that the method with the method steps (a.) - (e.) Is carried out after at least a first dishwashing detergent preparation, preferably an enzyme-containing dishwashing detergent preparation, was released into the interior of the dishwasher, wherein the release the at least first dishwashing detergent preparation takes place when at least one temperature> 25 °, preferably> 29 ° C and the presence of water has been detected. Method according to one of the preceding claims, characterized in that the method with the method steps (a.) - (e.) Is carried out after after the release of the first dishwashing detergent preparation at least a second dishwashing detergent preparation, preferably an alkaline dishwashing detergent preparation, in the interior of the dishwasher was released. Device for dosing a rinse aid preparation in the interior of a dishwasher comprising - a sensor for the detection of water - A sensor for detecting the temperature - A control unit for processing the sensor data wherein the control unit is configured to perform the method of any of claims 1-4. Apparatus according to claim 5, characterized in that the device is freely positionable by a user in the interior of a dishwasher. Device according to one of claims 5 to 6, characterized in that the device comprises a cartridge with at least one chamber in which at least one rinse aid preparation is stored. Apparatus according to claim 7, characterized in that the cartridge comprises at least three chambers in which an enzyme-containing preparation, an alkaline preparation and a rinse aid preparation are stored. Device according to one of claims 5 to 8, characterized in that the control unit with the existing control of the household appliance is in particular wirelessly coupled.

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