GARDEN APPLIANCE WITH ONE CONTROL UNIT AND METHOD FOR DISPLAYING CONTENT DEVICE EXTERNAL DATA SOURCES

Description

[0001] The present invention relates to a cooking appliance according to the preamble of claim 1, and to a method for displaying content from external data sources in a graphic display of a cooking appliance.

[0002] German patent application DE 10 2015 120 397 A1 discloses a cooking appliance of this type in the form of an induction cooktop with a glass-ceramic cooking surface and an integrated control and display unit. The control and display unit comprises a touchscreen display which, after a cooking zone is selected, displays two areas. One area shows selectable and adjustable operating information for the selected cooking zone.

[0003] From publication US 2015 / 0192302 A1, a control and display system for a household appliance is known, which has several interactive displays. An inactive zone is formed between each of the interactive displays.

[0004] EP 31 15 697 A1 D3 describes a control unit for a household appliance, which includes an input / output device designed as a display. The display can be switched between an operating mode and an information mode by means of a control element.

[0005] From DE 10 2018 131 031 A1, a device for assigning an assistance program to a cooking appliance is known. The device has a display unit that is divided into a first display area and a second display area. A sensor unit is provided to detect a swiping movement between the first and the second display area.

[0006] US patent 2015 / 185980 A1 discloses a smartphone on which two applications can be displayed simultaneously. A dividing line is shown between the two applications, which can be moved by the user, thus changing the size of the individual display areas.

[0007] The invention is based on the objective of improving the aforementioned state of the art.

[0008] This problem is solved by a cooking appliance having the features of claim 1. Furthermore, the problem is solved by a method having the features of claim 6. Advantageous embodiments are described individually or in combination in the dependent claims.

[0009] The device or method according to the invention is used in particular in a household appliance designed as a cooking appliance of the so-called "white goods", such as a stove or a hob.

[0010] The terms "top", "bottom", "front", "back", "horizontal", "vertical", "left", "right", "depth", "latitude", "height", etc. indicate the positions and orientations that would be present when the cooking appliance is used as intended and when viewed by an observer standing in front of the cooking appliance and looking towards the control unit or the cooking appliance.

[0011] According to the characterizing part of claim 1, the additional display mode can be activated as needed by a user action. The resulting second sub-area displays content that the control unit retrieves from an external data source. Each sub-area is bounded on three sides by a physical border of the graphic display. This creates clear structures and enables easy operation by the user, such as resizing the sub-areas by simply moving a separator bar. The additional display mode can be activated by the user as an extra or convenience function. This additional function is not strictly necessary for operating the cooking appliance. In the additional display mode, the operating information of the cooking appliance continues to be displayed in the first sub-area.The display of operating information is adapted to the now smaller display area. This is achieved by omitting non-essential information, reducing its size, and / or using nested displays. The amount of operating information displayed may depend on the size of the first section. The graphic display is a matrix display with individually addressable pixels. It is a touchscreen, meaning it is touch-sensitive.

[0012] The content displayed in the second section comprises instructions in the form of a cooking recipe. This allows users to conveniently compare the suggested settings for the cooking appliance with the actual settings in the adjacent first section and, if necessary, adjust or enter new settings. It is also possible, for example, to play instructional videos for cooking individual dishes on the second section. On a touchscreen display, the video can be paused at any time, for example, using a virtual pause button displayed on the screen or simply by tapping the screen. This allows users to follow the cooking process step by step without neglecting to monitor the cooking appliance.The user can quickly intervene in the cooking process at any time, especially while watching the instructional video. The cooking appliance is therefore always supervised, ensuring safe operation. Particularly convenient settings are achieved when the content of the two sections can be linked. This is the case, for example, when suggested operating parameters from the second section can be transferred directly to the first section by double-tapping, swiping, or activating a confirmation or transfer button, and then implemented by the control unit. Ideally, the control unit performs a plausibility check to prevent impermissible operating parameters.

[0013] The user preferably activates the additional display mode directly on the cooking appliance itself. This can be done, for example, by touching a virtual button displayed on the graphic display. However, it is also possible to activate it on an external multimedia device, such as a smartphone or tablet, which may be connected to the cooking appliance via an app. The content retrieved by the control unit from the external data source is transmitted to the cooking appliance wirelessly, for example, via a Wi-Fi or Bluetooth connection. The control unit is equipped with a communication module that enables the connection to the external data source. This communication module may utilize LAN, Wi-Fi, Bluetooth, or similar connection technologies.In addition to controlling the graphic display, the control unit is also designed to register input from the operating elements and to execute all control tasks of the cooking appliance, such as activation or power control of appliances. The operating elements are displayed as virtual controls on the graphic display, depending on the situation. Furthermore, a combination of physical and virtual controls is also possible.

[0014] The content displayed on the second sub-area can be selected by the user, for example, via a multimedia device such as a smartphone or tablet. This content is initially independent of the control unit and is not stored within it. In the case of a cooking appliance, the design according to the invention offers the particular advantage that no multimedia device is required in the immediate vicinity of the cooking appliance for the content displayed on the second sub-area; instead, the cooking appliance's own display capabilities are used. This prevents the multimedia device from becoming soiled, for example, during cooking. The cooking appliance's graphic display is typically resistant to soiling and is also easier to clean than an external multimedia device.The content displayed in the second section can also include social media content, the advantage of which lies in the ability to simultaneously monitor the cooking appliance while, for example, exchanging messages via a messenger service. This allows the user to immediately notice, for instance, pasta water boiling over, even while processing their messenger messages. They can then quickly intervene and, for example, reduce the power level of the relevant cooking zone.

[0015] The spatial division of the sub-areas in relation to the overall area of ​​the graphic display can be modified by a further user action. For example, the user can resize the display area of ​​the second sub-area according to the content to be displayed. The first sub-area is simultaneously and automatically adjusted in size, ensuring that the graphic display is always fully occupied by both sub-areas. Adjustments to the first sub-area are made by omitting or adding less relevant information and / or by nesting the individual pieces of information within each other.

[0016] A boundary between the sub-areas is defined by a user-movable separator symbol displayed on the graphic display. This separator symbol can, for example, be a dividing bar or line positioned between the first and second sub-areas. Preferably, on a landscape-oriented touchscreen, the user can move the separator bar left or right by touching it, thus defining the size of the respective sub-areas. The separator bar or line can be only indicated, extending across a portion of the screen width, or it can extend across the entire screen width. Instead of a dividing bar, a symbol, such as a geometric element like a rectangle, can also be displayed to the user.A color change between the two display areas can also indicate the separation between the two sub-areas to the user.

[0017] To prevent the user from selecting too small a size for the first section of the display, the control unit has a minimum size preset for the section showing operating information, which cannot be reduced. This ensures that the cooking appliance can always display all important operating information in the designated section. The minimum size essentially refers to a minimum length relative to the overall length of the graphic display, as this is the only part that can be changed by the user. The width is determined by the maximum width of the graphic display, which also defines the boundaries of the two sections. The length refers to the longer of the two sides of the essentially rectangular graphic display, and the width to the shorter side.It may also be provided that a further minimum size is defined for the second sub-area, below which the display of external device content would not make sense due to, for example, a font size that is too small.

[0018] If a user action would result in a display smaller than a predefined minimum size, a corresponding warning is displayed. This warning can be, for example, text displayed on the graphic display or a flashing or flickering separator bar. The control unit defines a maximum position for the separator symbol, beyond which it cannot be moved further into the first sub-area. At least the minimum necessary operating information must always be displayed in a sufficiently large format within this first sub-area. The size of this first sub-area can be adjusted by omitting or adding less relevant information and / or by nesting the individual pieces of information within each other.

[0019] To enable more convenient operation of the cooking appliance, a preferred embodiment may include a control element designed to display content from one section of the display in the other section when activated, and vice versa. According to the user's personal preference, the operating information of the cooking appliance can thus be displayed on either of the two sections of the graphic display. Preferably, the existing size or area ratios of the individual sections are maintained. For example, the left and right sections can be swapped. The same applies to a rectangular display oriented differently on the cooking appliance, for example, to an upper and a lower section.The control element can be a virtual control element that is displayed on the graphic display depending on the situation, but it can also be a physical control element that is located outside the graphic display on the cooking appliance.

[0020] Each sub-area is bounded on at least three sides by a physical edge of the graphic display. This creates clear structures and enables easy operation by the user, such as resizing the sub-areas by simply moving a separator bar.

[0021] A preferred embodiment consists in the graphic display having an aspect ratio of at least 3:2, preferably at least 2:1. Such a rectangular display is particularly well suited for division into two sections. The graphic display can, for example, be oriented in landscape format, parallel to a front edge of the cooking appliance. Alternatively, the graphic display can be oriented perpendicular to a front edge of the appliance in portrait format. In this case, the front edge of the appliance is parallel to a user standing in front of the cooking appliance.

[0022] In an advantageous embodiment of the invention, content to be displayed in the second sub-area can be selected by the user on a device external to the cooking appliance and transmitted to the control unit of the cooking appliance via a streaming architecture. Transmission can thus occur, for example, from a multimedia device such as a tablet or smartphone using Google Cast, Chromecast, Apple AirPlay, Apple CarPlay, Android Auto, Apple TV, or similar services. This has the advantage that the transmitted content is automatically and optimally adapted to the available display size of the second sub-area, ensuring a user-friendly and clear presentation. A corresponding utility, or several such utilities, for the necessary data exchange are stored in the control unit of the cooking appliance.

[0023] Furthermore, it is preferably possible to display a mirrored version of the multimedia device's screen on the second section of the cooking appliance's graphic display. This allows the user to access content from their multimedia device, at least partially, via the cooking appliance's graphic display. Advantages include the ability to play videos or view step-by-step instructions on the second section. It also enables the use of social media programs. All these possibilities for using the cooking appliance's graphic display offer the particular advantage of allowing the user to simultaneously monitor the cooking appliance's operation. Preventing the multimedia device from becoming dirty due to the often harsh conditions found around cooking appliances is another benefit.In a preferred embodiment, the control unit is designed to allow the user to transfer content from the second sub-area to the first sub-area. For example, in instructions such as a recipe or operating manual displayed in the second sub-area, the user can transfer operating settings to the first sub-area via drag and drop or a corresponding virtual button. These settings are then preferably adopted by the control unit after a plausibility check and used as active operating parameters for the operation of the cooking appliance.

[0024] In an advantageous embodiment of the invention, the cooking appliance is designed as a cooktop with a graphic display arranged behind a glass-ceramic surface. The graphic display is designed as a narrow, elongated, rectangular display, the longer side of which is arranged parallel to a front edge of the cooktop. This ensures that, despite the large display, sufficient space remains for the arrangement of even larger cooking zones. The controls are designed, for example, as capacitive touch controls, the components of which are also arranged behind the continuous glass-ceramic surface, which has no openings. Additional controls are displayed as virtual controls on the graphic display, depending on the situation.

[0025] Furthermore, the invention relates to a method for displaying content from external data sources in a graphic display of the aforementioned cooking appliance, comprising the following steps: Dividing the graphic display into a first and a second sub-area as a result of a user operation, each sub-area being bounded on three sides by a physical edge of the graphic display; retrieving content from an external data source by means of a control unit of the cooking appliance; displaying operating information of the cooking appliance on the first sub-area of ​​the graphic display in a representation adapted to the reduced display area by the control unit; displaying the content of the external data source on the second sub-area of ​​the graphic display and providing a means to change the spatial division of the sub-areas with respect to the total area of ​​the graphic display by means of a further user operation.

[0026] The control unit adjusts the operating display to the reduced screen area. This adjustment of the first section is achieved by omitting or adding less relevant information and / or by nesting the individual pieces of information within each other. The user can also operate the appliance while it is switched on by performing an action on an external device, such as a tablet or smartphone.

[0027] The size of the display areas of the sub-areas can be changed by moving a separator symbol displayed on the graphic display, thus providing a convenient way to adjust the display size of the two sub-areas to the user's needs. The separator symbol is visually represented on the graphic display, for example, as a dividing bar between the sub-areas. The user can tap and then drag this bar with their finger to change the size of the sub-areas accordingly.

[0028] Advantages and features described with regard to the cooking appliance apply - insofar as applicable - accordingly to the method according to the invention and vice versa.

[0029] Further features and advantages of the invention will become apparent from the following description of an exemplary embodiment with reference to the accompanying schematic figures. These show: Fig. 1 a cooktop with cooking zones and a control unit in a top view; Fig. 2 a graphic display of the control unit with an undivided display; Fig. 3 the graphic display with a division into two sub-areas and Fig. 4 the graphic display with a modified division of the two sub-areas.

[0030] In the figures, identical or functionally equivalent elements are given the same reference symbols.

[0031] Cooking zone 2 from Fig. 1The cooktop features a glass-ceramic plate 4 on which cooking zone markings for four cooking zones 6, 8, 10, and 12 are printed. Cooking vessels, such as pots or pans (not shown), can be placed on these cooking zone markings for heating. Below the cooking zone markings, on the other side of the glass-ceramic plate 4, corresponding heating elements (not shown) are arranged. A first cooking zone 6a is located at the rear left. This zone is circular and can be extended into an elongated cooking zone by means of a roasting tile extension 6b. A second circular cooking zone 8 is located at the rear right, and a third circular cooking zone 10a is located at the front right. The diameter of this third circular cooking zone can be increased by means of an extension zone 10b. Finally, a fourth cooking zone 12 is located at the front left.A control unit 14 is arranged in the center of a front area of ​​the hob 2, which has a power button 16, a split button 18, and a display device 20.

[0032] The display device 20 is designed as a graphic display 22. The two buttons 16 and 18 are each designed as capacitive touch-sensitive buttons. The graphic display 22, as well as sensor electronics for the two buttons 16 and 18, is located below the glass-ceramic plate 4. The graphic display 22 is designed as a touch-sensitive matrix display with touch functionality in the form of a touchscreen.

[0033] A control unit 24, located beneath the glass-ceramic cooktop 4 and thus out of sight of the user, is designed to control the entire cooktop 2. For example, the control unit 24 controls the entire operating unit 14. Specifically, this includes the touch-enabled graphic display 22, as well as the power button 16 and the split button 18, each of which preferably also has an integrated indicator light. Furthermore, in response to user input on the graphic display 22, the control unit 24 can activate the roasting extension 6b for cooking zone 6a, or the extension zone 10b for cooking zone 10a, and connect it to the cooking zone 10a in terms of power. The control unit also regulates the heating elements assigned to the individual cooking zones 6, 8, 10, and 12 according to the power levels assigned to those zones.The graphic display 22 is divided into a first sub-area 26a and a second sub-area 26b. A separator symbol 28 in the form of a dividing bar is displayed between the two sub-areas 26a and 26b. This dividing bar symbol 28 can be moved by the user by touching it with a finger and then sliding it to the right or left, thereby changing the relative area of ​​sub-areas 26a and 26b. The first sub-area 26a displays the operating information of the cooktop 2, such as the power levels assigned to the individual cooking zones 6, 8, 10, and 12. The second sub-area 26b displays cooking instructions for the user.

[0034] The graphic display 22 in a detailed view shows Fig. 2 .The dimensions of the rectangular graphic display 22 are defined by a length l and a width b, which have a ratio of approximately 3:1. The graphic display 22 shows a basic display mode in which only the operating settings of the cooktop 2 are displayed. Thus, the entire surface of the graphic display 22 is used exclusively for displaying operating information. This is particularly the case immediately after the cooktop 2 is switched on using the power button 16. Analogous to the geometric division of the individual cooking zones 6, 8, 10, and 12 on the glass-ceramic cooktop 4, the corresponding cooking zone symbols 60, 80, 100, and 120 are arranged in the same geometric arrangement in the center of the graphic display 22. A corresponding cooking zone symbol 60a is provided for the left rear cooking zone 6, and a corresponding symbol 60b for the roasting zone extension 6b.Cooking zone 8 is represented by the cooking zone symbol 80. Cooking zone 10a is represented by the cooking zone symbol 100a, and extension zone 10b by the extension zone symbol 100b. Cooking zone 12, located at the front left, corresponds to cooking zone symbol 120, which is also displayed at the front left of the graphic display 22 in relation to the other cooking zone symbols 60, 80, and 100. Active cooking zones 6, 8, 10, and 12, or cooking zone areas in heating mode, can be highlighted by the control unit 24 with respect to the cooking zone symbols 60, 80, 100, and 120, for example, by color, higher contrast, or a wider line.

[0035] In addition to the cooking zone symbols 60, 80, 100, and 120, further information is displayed to the user in a straight line. This includes, for example, a timer symbol 32 and, next to it, the corresponding timer display 60T, 100T, and 120T. Subsequently, as soon as the corresponding cooking zone 6, 8, 10, or 12 exceeds a minimum temperature, a residual heat symbol 30 is displayed. Between the residual heat symbol 30 and the associated cooking zone symbols 60, 80, 100, and 120, the power indicator 60L, 80L, 100L, and 120L is shown. In this embodiment, cooking zone 10 is also equipped with a frying sensor (not shown), which is indicated by a frying sensor symbol 34 when activated. Fig. 2The graphic display shown on screen 22 is the one of several possible display modes that shows the most detailed or comprehensive operating information. This display is optimized for standard operation of the cooktop, i.e., when no additional external content is to be displayed.

[0036] After the user activates the split button 18, the graphic display 22 will be adjusted accordingly. Fig. 3The display is divided into a first sub-area 26a and a second sub-area 26b. A separator symbol 28 is positioned between the two sub-areas 26a and 26b, and its position can be moved by the user. The first sub-area 26a continues to display the operating information, but now in a simplified format. For example, the power levels 60L, 80L, 100L, and 120L are displayed within the respective cooking zone symbols 60, 80, 100, and 120. Next to the cooking zone symbols 60, 80, 100, and 120, the timer symbol 32 and the timer displays 60T, 100T, and 120T are also shown. A numerical timer display 60T for cooking zone 6 is not shown because no timer has been activated for cooking zone 6. For reasons of space, the residual heat symbol 30 is not displayed during the regular operation of the respective cooking zones 6, 8, 10 and 12.This is now only displayed alongside the cooking zone symbols 60, 80, 100, and 120 when cooking zones 6, 8, 10, and 12 are switched off, provided there is sufficient residual heat. The second section, 26b, displays cooking instructions or a recipe, which the control unit 24 has retrieved from an external data source.

[0037] If the display of the second section 26b, i.e., the recipe, is too small for the user, they can touch the separator symbol 28 with their finger and move it to the left. This enlarges the second section 26b accordingly, thus enlarging the recipe and displaying it with more detail, as shown in Fig. 4The separator symbol 28 is preferably continuously movable, with a maximum position of the separator symbol 28 defined in the control unit 24, beyond which it can no longer be moved further towards the first sub-area 26a. This ultimately defines a minimum display area for the first sub-area 26a in the control unit, ensuring proper display of the operating parameters in all cases. This means that at least the minimum necessary operating information can always be displayed in a sufficiently large format in the first sub-area 26a.

[0038] In the Fig. 4Due to the minimal size of the first sub-area 26a shown, the operating parameter displays are reduced to a minimum. Only the power levels assigned to the individual cooking zones 6, 8, 10, and 12 (60L, 80L, 100L, and 120L) are now displayed within the cooking zone symbols 60, 80, 100, and 120, respectively. By touching one of these symbols, the user can then display more detailed operating information for the respective cooking zone. The power setting and / or the time setting for the individual cooking zones 6, 8, 10, and 12 are also accessible, for example, by opening a corresponding submenu (not shown) when the user touches one of these symbols. The information presented in the second subsection 26b can preferably be used analogously to a smartphone, orThe tablet can be scrolled, moved, resized, enlarged, and rearranged by a user's finger. Sub-areas 26a and 26b each extend across the full width b of the graphic display 22.

[0039] After switching on the cooktop 2 with the power button 16, the user initially only sees the operating information displayed in detail. However, they can also display step-by-step instructions, such as a cooking recipe, by first pressing the corresponding split button 18. Triggered by a smartphone app on a smartphone or tablet connected to the cooktop, the control unit 24 is then instructed to retrieve the relevant data from an external source. The control unit 24 is also preferably designed to create and display the second sub-area 26b based on an action performed by the user on a device external to the cooktop. For example, the user can select a corresponding cooking recipe via an app on their smartphone and then have it displayed in the second sub-area 26b of the graphic display 22 on the cooktop 2.This is achieved via a streaming architecture present in the smartphone and / or in the control unit 24 of the cooktop 2. It is also possible for the user to transmit the screen content of their smartphone to the second section 26b of the graphic display 22, for example, via Google Cast, Apple CarPlay, or a similar service with corresponding control options. The user can then, for instance, reply to messages addressed to them from social media platforms directly on the cooktop 2, while still monitoring the cooking process. Furthermore, this advantageously prevents the smartphone from becoming dirty due to the user's cooking activities. Streaming videos to the second section 26b is also possible. Reference symbol list:

[0040] 2 Cooking zone 4 Glass ceramic plate 6a Cooking zone 6b Roasting zone extension 8 Cooking zone 10a Cooking zone 10b Extension zone 12 Cooking zone 14 Control unit 16 On / off button 18 Split button 20 Display device 22 Graphic display 24 Control unit 26a First section 26b Second section 28 Separation symbol 30 Residual heat symbol 32 Timer symbol 34 Roasting sensor symbol 60a Cooking zone symbol 60b Roasting zone extension symbol 60L Power indicator 60T Timer display 80 Cooking zone symbol 80L Power indicator 100a Cooking zone symbol 100b Extension zone symbol 100L Power indicator 100T Timer display 120 Cooking zone symbol 120L Power indicator 120T Timer display b Width l Length

Claims

1. Cooking appliance, with an operating unit (14), which has operating elements (16, 18) and a display apparatus (20) designed as a graphic display (22), with a control unit (24) which controls the graphic display (22) for displaying operating information and provides an additional display mode of the operating unit (14), in which display mode the graphic display (22) is split into two separate subregions (26a, 26b), of which a first subregion (26a) displays the operating information in an adjusted presentation, wherein each subregion (26a, 26b) is limited on three sides by a physical edge of the graphic display (22), the graphic display (22) is designed as a touchscreen and the control unit (24) is configured to detect an input on the operating elements, and to perform all control tasks of the cooking appliance, and the operating elements are presented as virtual operating elements on the graphic display depending on the situation, wherein the additional display mode can be activated as required by an operator action by a user, and the second subregion (26b) formed thereby presents content items retrieved by the control unit (24) from an external data source, the content item presented in the second subregion comprises instructions in the form of a recipe so that a user can compare settings for the cooking appliance proposed in the instructions with the actual setting values directly via the adjacent first subregion (26a) and, if necessary, readjust or input setting values, characterised in that the spatial distribution of the subregions (26a, 26b) in respect of a total area of the graphic display (22) can be altered by way of an additional user operator action, wherein a boundary between the subregions is defined by way of a divider icon (28) which can be shifted by a user and which can be displayed in the graphic display, and wherein, in the control unit (24), a maximum position of the divider icon (28) is defined, in which the divider icon cannot be shifted any further in the direction of the first subregion 26a, wherein at least the minimal necessary operating information can always be displayed in a sufficiently large presentation in the first subregion 26a, and the adjustment of the first subregion is carried out by omitting or adding less relevant information and / or by nesting the individual items of information within each other.

2. Cooking appliance according to one of the preceding claims, characterised in that an operating element is provided which is configured, after activation, to display a display content item of the one subregion (26a, 26b) in the other subregion (26a, 26b) and vice versa.

3. Cooking appliance according to one of the preceding claims, characterised in that the graphic display (22) has an aspect ratio of a length (1) to a width (b) of at least 3:2, preferably at least 2:1.

4. Cooking appliance according to one of the preceding claims, characterised in that a content item to be presented in the second subregion (26a, 26b) can be selected by way of an operator action by the user on a device which is external to the household appliance and which content item can be transferred to the control unit (24) of the household appliance by means of a streaming architecture.

5. Cooking appliance according to one of the preceding claims, characterised in that this is designed as a hob (2) with a graphic display (22) arranged behind a glass-ceramic plate (4).

6. Method for displaying content items from appliance-external data sources in a graphic display (22) of a cooking appliance according to one of the preceding claims, comprising the following steps: - splitting the display of the graphic display into a first and a second subregion (26a, 26b) as a result of an operator action by a user, wherein each subregion (26a, 26b) is limited on three sides by a physical edge of the graphic display (22), - retrieving content items from a data source external to the appliance by means of the control unit (24) of the cooking appliance; - displaying operating information of the cooking appliance on the first subregion (26a, 26b) of the graphic display (22) in a presentation that is adjusted to the display area which is reduced in size by way of the control unit, - displaying the content items of the data source external to the appliance on the second subregion (26a, 26b) of the graphic display and - providing an opportunity for altering the spatial distribution of the subregions (26a, 26b) in respect of a total area of the graphic display (22) by way of an additional operator action by the user, wherein the size of the display area of the subregions (26a, 26b) can be altered by way of a sliding movement of a divider icon (28) displayed in the graphic display (22) up to a boundary defined in the control unit (24).