EP2400224B1 - Household device with a control unit - Google Patents

Description

The invention relates to a domestic appliance with a control unit according to the preamble of claim 1.

Domestic appliances, for example cooktops, which comprise one or more power units, such as heating zones or heating elements, are known from the prior art. Such home appliances include a control unit for operating the power unit. The control unit can be designed as a universally programmable arithmetic unit that can use, for example, a driver module with power electronics components for actuating the power units. Further, generic home appliances include a user interface for selecting a power level of the power unit from a number of discrete power levels. In particular, the control unit is designed by suitable software to use at least one power allocation function to determine a desired power for operating the power unit depending on the selected power level. Such household appliances are from the EP 1 273 851 A2 and the DE 10 2005 040 346 A1 known.

The object of the invention is in particular to equip a generic home appliance with improved ease of use for various types of users and to achieve a simple setting.

The object is achieved by the features of claim 1, while advantageous embodiments and modifications of the invention can be taken from the dependent claims.

The invention is based on a domestic appliance with a control unit and a user interface for selecting a stage from a number of power stages for setting a step-adjustable operating parameter, wherein the control unit is adapted to use at least one assignment function to the operating parameter depending on the selected stage wherein the user interface comprises at least one setting means for changing the assignment function. This allows the operator or user, the assignment function to its individual Adjust needs, whereby the ease of use for various types of users, especially with conflicting preferences or needs can be increased. For example, a user who does not place an emphasis on precise adjustment of the operating parameter, and therefore requires only a few power levels, can choose a few-power mappings function, while a user who cares about a precise setting would be willing to accept a more complex set-up , can choose a high-resolution mapping function with a variety of performance levels.

It is proposed that the domestic appliance has a plurality of operating parameters, which may be, for example, heating stages of different heating zones of a hob, each having an allocation function, wherein the setting means is designed to simultaneously change the assignment functions of all operating parameters. As a result, in particular a simple adjustment can be achieved.

The concept of the invention can be used, in particular, in domestic appliances which comprise at least one power unit, wherein the stage can then determine a nominal power of the power unit during operation.

A gain in comfort can be achieved by the flexibly adjustable assignment function, in particular if the user interface comprises a key for incrementing the stage and a key for decrementing the stage. In such user interfaces, a large number of high-power levels can be annoying to users who do not care about high-resolution.

In particular, in domestic appliances, which are designed as cooking appliances, in particular as hobs, and in which the power unit is designed as a heating element, such incrementing and decrementing keys are widely used. In this case, the stage is a heating stage and the target power is a desired heating capacity. However, the idea of the invention would also be applicable, for example, to washing machines, vacuum cleaners or the like, the power unit then being a motor. Furthermore, an application of the invention in electrical radiators or air conditioning systems would be conceivable that could be formed, for example, as a motor vehicle air conditioning systems.

The mapping function can be made flexible if the domestic appliance is equipped with at least one memory unit for storing at least two assignment functions. The assignment functions can either be stored in the form of different parameters of a parametric basic function or as tables. Any representation and storage of the assignment function which appears expedient to the person skilled in the art is conceivable.

In an advantageous embodiment of the invention, the household appliance comprises a memory unit for storing at least one list of values which are each associated with a level and which are used by the control unit as parameters of the assignment function. The values may, for example, correspond to a percentage of the target power at a maximum power of the power unit.

The resolution of the mapping function can be easily adapted to the needs of the user if the setting means is designed to set the number of power levels.

Unnecessary complexity can be avoided if the setting means is designed to select one of two or three possible values for the number of power levels.

Intuitive operation of the domestic appliance can be ensured in particular for the various assignment functions if the values of the various assignment functions are distributed at least substantially evenly between zero and a maximum nominal output of the power unit.

A simple transmission of the assignment functions to a plurality of operating parameters, each with an assignment function, can be made possible if the assignment functions differ in each case only by a constant factor.

The setting can be further simplified if the various operating parameters, which may be, for example, heating stages of different heating zones of a hob, are controllable via a respective assignment function, wherein the setting means can then be designed in particular for simultaneously changing the assignment functions of all power units.

Further improved ease of use can be achieved if the user interface comprises a display for displaying a selection menu for changing the assignment function.

Further advantages emerge from the following description of the drawing. In the drawing, an embodiment of the invention is shown. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations.

Fig. 1

ein Kochfeld mit vier Heizzonen und einer Benutzerschnittstelle,

Fig. 2

ein erstes Menü zur Auswahl von Grundeinstellungen,

Fig. 3

ein zweites Menü zur Änderung einer Zuordnungsfunktion und

Fig. 4

eine graphische Darstellung verschiedener Zuordnungsfunktionen des Kochfelds aus Figur 1.

Show it:

Fig. 1

a hob with four heating zones and a user interface,

Fig. 2

a first menu for selecting basic settings,

Fig. 3

a second menu to change a mapping function and

Fig. 4

a graphical representation of different mapping functions of the hob FIG. 1 ,

FIG. 1 shows a domestic appliance, namely a hob, with four power units 10a - 10d. The power units 10a-10d are heating elements of a heating zone. The heating elements may be formed, for example, as induction heating elements or as radiant heaters and are arranged under a cover plate 12 made of glass or glass ceramic.

The home appliance further comprises a control unit 14 for operating the power units 10a-10d. The home appliance is operable via a touch screen user interface 16 for selecting power levels of the power units 10a-10d from a number of power levels. The control unit 14 is designed by suitable software to use at least one power allocation function 20, to determine a target power for operating the power unit 10a-10d depending on the selected power level.

According to the invention, it is in particular proposed that the user interface 16 comprises at least one setting means 18 for changing the assignment function 20. This allows the operator or user to adapt the mapping function 20 to his individual needs.

The touchscreen user interface 16 includes a first button 22 for incrementing the power level and a second button 24 for decrementing the power level. By the setting means 18, the user can in particular determine a number of possible power levels.

Since the domestic appliance is designed as a cooktop and the power unit 10a-10d as a heating element, the power level corresponds to a heating stage and the desired power corresponds to a desired heating power, which serves as a reference variable for a temperature control or as a parameter for controlling the heating element. The heating element can be switched on and off periodically by the control unit 14, for example, in order to generate the desired heating power over the time average.

The control unit 14 comprises a memory unit 26 designed as a ROM or RAM memory for storing at least two assignment functions 20.

In particular, the memory unit 26 comprises memory locations for storing a list of 17 values explicitly specified below in an example, each of which is assigned to one of 17 power stages other than power level zero. The values are used by the control unit 14 or by an operating program implemented in the control unit 14 as a parameter of the assignment function 20.

The values are stored as floating point numbers and correspond to an expressed relationship between the desired power and a maximum power of the power unit 10a-10d. When the corresponding power level is set, the control unit 14 operates the power unit 10a-10d at a target heating power, which corresponds to the percentage of maximum power given by the value.

The control unit 14 controls, via a corresponding interface and a suitable driver, the user interface 16 embodied as a touch screen. The operating program which is executed on the control unit 14 represents various nested selection menus, in particular a FIG. 2 illustrated menu for selecting basic settings, for setting a language, parameters of a parental control and parameters of a power grid through which the cooktop is operated, the latter parameters include a supply voltage and a maximum power. In particular, in the menu of the basic settings, there is an entry 28 for changing the assignment function 20, for setting a number of performance levels. The touch screen therefore forms, in interaction with the control unit 14 and a driver of the touch screen and with the software of the control unit 14, a user-operable setting means 18 for setting the number of power levels.

If the operator in the in FIG. 2 displayed menu by touching the touch screen in the in FIG. 2 hatched area has selected the menu item or entry 28 for setting the number of power levels, the in FIG. 3 selection menu in which the operator can select one of three possible values for the number of power levels.

In addition to the maximum of 17 power levels and an average of 12 power levels, the operator can select a small number of 9 power levels. In the last-mentioned numerical values, the always adjustable power level zero is not included in each case. Each choice corresponds to one of three possible modes of operation, each with a different assignment function 20.

The storage unit 26 stores three lists with three allocation functions 20 corresponding to the three possible modes of operation. The assignment functions 20 or the lists can also be combined into a multi-column list.

The values of the assignment function 20 are in each case distributed at least substantially uniformly in a function that increases more than linearly between zero and a maximum setpoint power of the power unit 10a-10d.

Furthermore, the control unit 14 comprises a timing arrangement 30 which is realized as a timer function and which starts or is reset to zero when a power unit 10a-10d is switched on or when the power stage is switched over. Timing assembly 30 is for measuring an uninterrupted operating time of a power unit 10a-10d of the domestic appliance. If several power units 10a-10d are operated simultaneously, a plurality of timer functions run in parallel accordingly.

Furthermore, the control unit 14 is equipped with a means 32 implemented as an emergency shutdown function in the software for automatically switching off the power unit 10a-10d after the expiry of a maximum uninterrupted operating time of the power unit 10a-10d. The control unit 14 is therefore designed to determine the maximum uninterrupted operating time depending on the values in the list, since the list assigns a maximum operating time to the percentage of the maximum power. The maximum operating time is a monotonically decreasing function of the value describing the percentage of the maximum power in the list.

The following is an example of a possible association between the values, the power levels, and the maximum operating time. In this embodiment, it can be seen that in the operating modes with a medium and low (minimum) number of power levels, one select or one part Use power stages that are used in the operating mode with the maximum number of power levels for operating the heating elements. It can also be seen that the value which describes the percentage of the maximum heating power of the power elements increases significantly more than linearly with the selected power level. In the last line of the table, a booster function of the cooktop is mentioned in which the heating power can be briefly increased beyond the nominal heating power of the power element. Value (%) Performance level (Max) Performance Level (Medium) Power level (min) Max. Operating time (hours) 0.0 0 0 - - 3.1 1 1 1 4 4.7 2 - - 4 6.3 3 2 2 4 7.8 4 3 - 4 10.9 5 4 3 4 12.5 6 5 - 4 15.6 7 6 4 4 18.8 8th 7 5 4 21.9 9 8th - 4 25.0 10 - - 4 29.7 11 9 6 3 35.9 12 - - 3 43.8 13 10 7 2 53.1 14 - - 2 64.1 15 11 8th 1 79.7 16 - - 1 100.0 17 12 9 1 booster - - - 1

The allocation function 20 is stored in the form of the abovementioned percentages of the maximum power of the power units 10a-10d, the maximum power of the different power units 10a-10d being different. As a result, the same list can be used for all four power units 10a-10d, the absolute values of the assignment functions 20 each differing only by a constant factor which corresponds to the ratio of the maximum powers of the power units 10a-10d.

The settings made via the setting means 18 are therefore used to simultaneously change the assignment functions 20 of all the power units 10a-10d.

In alternative embodiments, the mapping functions 20 may be stored as mathematical functions that may be dependent on a parameter stored in the memory unit 26. By made on the adjusting means 18 Settings, the function can be selected or the parameter used of a parametric mapping function 20 can be changed.

• Figur 4 zeigt ein Koordinatensystem mit drei Graphen, die jeweils eine der drei möglichen Zuordnungsfunktionen 20a, 20b, 20c am Beispiel eines Heizelements mit einer Maximalleistung von 500W illustrieren. Die durchgezogene Linie beschreibt die Zuordnungsfunktion 20a mit der geringsten Anzahl von 9 Leistungsstufen, die gestrichelte Linie beschreibt die Zuordnungsfunktion 20b mit der mittleren Anzahl von 12 Leistungsstufen und die gepunktete Linie beschreibt die Zuordnungsfunktion 20c mit der höchsten möglichen Zahl von 17 Leistungsstufen. Die den Leistungsstufen L entsprechenden Heizleistungen H gemäß der Zuordnungsfunktionen 20a, 20b mit der jeweils geringeren Anzahl von Leistungsstufen L bilden eine Teilmenge der Heizleistungen H gemäß mit der Zuordnungsfunktion 20c mit der höchsten Zahl von Leistungsstufen L.
• Figur 5 illustriert die Abhängigkeit von der maximalen Dauer des Betriebs einer Heizzone mit einer Sollheizleistung, die einem vorgegebenen prozentualen Anteil A an der maximale Heizleistung H_max entspricht. Für geringe Anteile A bzw. für geringe Heizleistungen H beträgt die maximale Dauer vier Stunden und für hohe Heizleistungen eine Stunde. Die Dauer wird abhängig von dem gemäß gewählten Zuordnungsfunktion bestimmten Anteil A und nicht unmittelbar abhängig von der eingestellten Leistungsstufen L bestimmt. Dadurch wirkt die Sicherheitsabschaltung unabhängig von der vom Benutzer getroffenen Wahl der Anzahl der Leistungsstufen.
• Figur 6 illustriert ein in dem Kochfeld implementiertes Verfahren zur Verarbeitung einer über die Benutzerschnittstelle 16 eingestellten Leistungsstufe L. In einem ersten Schritt empfängt die Steuereinheit 14 die Leistungsstufe L von der Benutzerschnittstelle 16 und liest einen Parameter P aus dem Arbeitsspeicher oder aus einem Festspeicher. Der Parameter P hat drei mögliche Werte, die jeweils einer der möglichen Einstellungen "Maximal", "Mittel", "Minimal" zur Anzahl der Leistungsstufen L gemäß Figur 3 entsprechen.

The various menus on the touchscreen can be displayed in list form or, for example, by means of cyclically interchangeable entries, whereby only one entry is displayed at a time and the displayed entry can be swapped over by the use of cursor keys. In further alternative embodiments, the adjusting means 18 may be formed as an electromechanical switch.

• FIG. 4 shows a coordinate system with three graphs, each illustrating one of the three possible assignment functions 20a, 20b, 20c using the example of a heating element with a maximum power of 500W. The solid line describes the assignment function 20a with the least number of 9 power levels, the dotted line describes the allocation function 20b with the average number of 12 power levels, and the dotted line describes the allocation function 20c with the highest possible number of 17 power levels. The heat outputs H corresponding to the power levels L according to the assignment functions 20a, 20b with the respective smaller number of power levels L form a subset of the heating powers H according to the assignment function 20c with the highest number of power levels L.
• FIG. 5 illustrates the dependence on the maximum duration of operation of a heating zone with a desired heating power, which corresponds to a predetermined percentage A of the maximum heating power H _max . For low proportions A or for low heat outputs H, the maximum duration is four hours and for high heat outputs one hour. The duration is determined as a function of the proportion A determined according to the selected assignment function and not directly as a function of the set power level L. As a result, the safety shutdown is independent of the user's choice of the number of power levels.
• FIG. 6 illustrates a method implemented in the cooktop for processing a power level L set via the user interface 16. In a first step, the control unit 14 receives the power level L from the user interface 16 and reads a parameter P from the random access memory or from a read only memory. The parameter P has three possible values, each one of the possible settings "maximum", "average", "minimum" to the number of power levels L according to FIG. 3 correspond.

In a next step, the control unit 14 selects, depending on the parameter P, a mapping function 20 which is in Fig. 6 with f _P (L), and determines the percentage A according to A = f _P (L) using the selected assignment function.

In two further steps, the control unit 14 uses the percentage A determined in this way, on the one hand to determine the heating power H by the multiplication of the proportion A (possibly divided by 100%) with the maximum heating power H _max and, on the other hand, the maximum operating time depending on the percentage A to determine.

Finally, the actual operation is started and the relevant heating element is operated with the heating power H thus determined. A timer counts backwards from the maximum operating time and shuts off the heating element when the remaining zero time is reached.

In other embodiments of the invention, the customizable mapping function may be implemented in other home appliances such as a washing machine or oven. In a washing machine, the power levels may correspond to wash temperatures or a speed of a spin cycle. In an oven, the power level can be used to adjust the temperature. Furthermore, it is conceivable that the desired temperature of a refrigerator can be selected via the choice of the power level. In coffee machines can be selected by the choice of power level, for example, a quantity of water or a quantity of coffee.

10

Leistungseinheit

12

Abdeckplatte

14

Steuereinheit

16

Benutzerschnittstelle

18

Einstellmittel

20

Zuordnungsfunktion

22

Taste

24

Taste

26

Speichereinheit

28

Eintrag

30

Zeitmessanordnung

32

Mittel

reference numeral

10

power unit

12

cover

14

control unit

16

User interface

18

adjustment

20

mapping function

22

button

24

button

26

storage unit

28

entry

30

Time measuring arrangement

32

medium

Claims (13)

1. Household device with a control unit (14) and a user interface (16) for selecting a level from multiple levels for adjusting an incremental adjustable operating parameter, wherein the control unit (14) is designed to use at least one assignment function (20) to determine the operating parameter as a function of the selected level, wherein the user interface (16) comprises at least one adjustment unit (18) for changing the assignment function (20), characterised by a plurality of operating parameters, each with an assignment function (20), wherein the adjustment unit (18) is designed for simultaneously changing the assignment functions (20) of all operating parameters.
2. Household device according to claim 1, characterised in that the household device comprises at least one power unit (10a - 10d) and in that the level is a level, by means of which a target power of the power unit (10a - 10d) is determined in operation.
3. Household device according to claim 1 or 2, characterised in that the user interface (16) comprises a button (22) for incrementing the level, and a button (24) for decrementing the level.
4. Household device according to one of the preceding claims, characterised in that the household device is designed as a cooking device, in particular as a hob, wherein the level is a heating level and the target power is a target heating power of a power unit (10a - 10d) designed as a heating element.
5. Household device according to one of the preceding claims, characterised by at least one memory unit (26) for storing at least two assignment functions (20).
6. Household device according to one of the preceding claims, characterised by a memory unit (26) for storing at least one list of values, each of which is assigned to a level and can be used by the control unit (14) as parameters of the assignment function (20).
7. Household device according to claim 6, characterised in that the values correspond to a percentage of a target power at a maximum power of a power unit (10a - 10d).
8. Household device according to claim 2 and according to claim 6 or 7, characterised in that the control unit (14) comprises a time-measuring arrangement (30) for measuring a continuous operating time of the household appliance and a means (32) for automatically switching off the power unit (10a - 10d) on expiry of a maximum continuous operating time of the power unit (10a - 10d), wherein the control unit (14) is designed to determine the maximum continuous operating time as a function of the values in the list.
9. Household device according to one of the preceding claims, characterised in that the adjustment unit (18) is designed for adjusting the number of selectable levels.
10. Household device according to claim 8, characterised in that the adjustment unit (18) is designed for selecting one of two or three possible values for the number of levels.
11. Household device according to one of the preceding claims, characterised in that the values of the assignment function (20) are at least essentially distributed uniformly between zero and a maximum target power of a power unit (10a - 10d).
12. Household device according to one of the preceding claims, characterised by a plurality of operating parameters, each with an assignment function (20), wherein the assignment functions (20) differ in each case only by a constant factor.
13. Household device according to one of the preceding claims, characterised in that the user interface (16) comprises a display for displaying a selection menu for changing the assignment function (20).

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