Tastenfeld

Abstract

Keypad for an operating unit of a security application comprising at least one key (2) with a keycap (20), a first touch-sensitive sensor (5) and a second touch-sensitive sensor (6), wherein the first touch-sensitive sensor (5) and the second touch-sensitive sensor (6) are arranged such that a touch of the keycap (20) and / or a force applied to the keycap (20) with a human finger or an input element can be detected simultaneously by means of the first touch-sensitive sensor (5) and by means of the second touch-sensitive sensor (6), characterized in that the keycap (20) is at least partially transparent and a display unit is arranged below the keycap (20), wherein the first touch-sensitive sensor (5) and the display unit (6) are together designed as a touch-sensitive display unit.the second touch-sensitive sensor (6) is designed as a switching film comprising a separating layer (60) and two conductive layers (61, 62) separated in the rest state by means of the separating layer (60), and the touch-sensitive display unit is arranged below the switching film.

Description

SCOPE OF APPLICATION AND STATE OF THE ART

[0001] The invention relates to a keypad for an operating unit of a security application with at least one key, an operating unit with a keypad and the use of a keypad in an operating unit.

[0002] In the context of registration, a key refers to an actuating element that can be mechanically or manually activated by touch or pressure. Depending on the application, the key is designed as a momentary switch, in particular as a normally open or normally closed switch, which automatically returns to its initial state after the removal of touch or applied force, or as a changeover switch, which remains in a changed switching state after activation. A keypad is a unit comprising at least one key.

[0003] For control units in safety applications, it is common practice to implement relays, pushbuttons, and / or changeover switches with two or more electromechanical contacts. To avoid the risk of a faulty trip due to a contact defect, such as a contact failing to open due to welding, the contacts are mechanically coupled. Such mechanically coupled contacts are also referred to as positively guided contacts.

[0004] Due to their electromechanical design, such pushbuttons with positively guided contacts require a relatively large installation space and often have a limited maximum number of switching cycles. Furthermore, in redundant pushbuttons, the contacts must be monitored and diagnosed to detect a contact failure.

[0005] From DE 10 2009 036 860 A1, an operating unit comprising at least one button with a movable key element, at least one display, and at least one transparent, touch-sensitive input field is known, wherein the at least one input field is connected to the key element in such a way that when the at least one input field is actuated, the at least one button can be actuated simultaneously, and wherein the at least one display is visible through the at least one input field or through the at least one input field and the key element.

[0006] DE 20 2012 006 899 U1 describes an agricultural machine with a control device for controlling operating parameters, and an end device for inputting control commands for the control device, which end device includes several operating buttons for inputting control commands for various control functions, wherein switching means for changing the key assignment of the respective operating button with different control functions and display means for displaying the respective selected key assignment are provided, and wherein the display means have display elements arranged directly on the operating buttons for displaying the respective key assignment directly on the respective operating button.

[0007] From DE 102020212536 A1 a button for safety applications is known, comprising an operating surface, a first touch-sensitive sensor and a second touch-sensitive sensor, wherein the first touch-sensitive sensor and the second touch-sensitive sensor are arranged such that a touch of the operating surface and / or a force input on the operating surface with a human finger or an input element can be detected simultaneously by means of the first touch-sensitive sensor and by means of the second touch-sensitive sensor.

[0008] US 5,132,496 A describes a membrane switch assembly comprising a support element on which upper and lower membranes are provided, the membranes bearing mutually aligned contacts, the membranes being held apart by a separating membrane having an opening oriented toward the aligned contacts. The membrane switch assembly further comprises an actuating element for selectively bringing one of the contacts into contact with another through the opening in the separating membrane, the actuating element comprising a release element and an operating block surrounding the release element and having a lower surface that contacts the upper, contact-bearing membrane in a region not located above the opening.

[0009] DE 44 98 145 C1 describes a rollable flat input keyboard for data processing devices, which, starting from the side facing away from the operating side, has successively a support layer, an electrical switching function system with electrical contact points corresponding to a keyboard pattern, and a flexible elastic cover layer provided with the keyboard pattern on the operating side facing away from the switching function system, wherein the support layer, the switching function system, and the cover layer are connected to each other at least along the circumferential edge, and wherein the switching function system is provided with predetermined bending lines, which are created by segmenting one or more film layers.

[0010] US 2007 / 0163866 A1 describes a printed circuit board with thin-film switches for a keyboard, comprising an upper plate with multiple circuit traces, an insulating separation defining multiple through-holes, a lower plate with multiple circuit traces, and multiple thin-film switches mounted on the upper and lower plates. TASK AND SOLUTION

[0011] One object of the invention is to create a keypad for a control unit of a security application, which is configurable for intuitive use. Further objects are to create a control unit with a keypad and the use of a keypad in a control unit.

[0012] According to a first aspect, a keypad for an operating unit of a security application is created, comprising at least one key with a keycap, a first touch-sensitive sensor and a second touch-sensitive sensor, wherein the first touch-sensitive sensor and the second touch-sensitive sensor are arranged such that a touch of the keycap and / or a force applied to the keycap with a human finger or an input element can be detected simultaneously by means of the first touch-sensitive sensor and by means of the second touch-sensitive sensor, wherein the keycap is at least partially transparent and wherein a display unit is arranged below the keycap, wherein the first touch-sensitive sensor and the display unit together form a touch-sensitive display unit, wherein the second touch-sensitive sensor is a switch film comprising a separating layer and twoconductive layers, in particular two carbon layers, layers with conductive paste, metallized layers and / or metal layers, separated in the resting state by means of the separating layer, and wherein the touch-sensitive display unit is located below the switch film.

[0013] The terms "a", "an", etc. are used in the context of registration only as indefinite articles and not as counter words. In particular, the keypad may contain more than one key in certain configurations.

[0014] In the context of registration, a display unit is an electrically controlled display unit for the optical signaling of changing information such as images or characters and / or their colors. The display unit allows the appearance of the key to be customized, so that the key has an appearance that can be defined by the user and / or in a configuration, depending on the application.

[0015] "Below the keycap" refers to an arrangement on one side opposite the actuation side of the keycap. Depending on the application, the display unit can be positioned to the left, right, and / or above the keycap.

[0016] At least two of the two or more sensors are designed as touch-sensitive sensors. In the context of this application, touch-sensitive sensors are defined as electronic systems for detecting contact with the keycap and / or force applied to the keycap by a human finger or an input element. Such sensors are also referred to as touch sensors.

[0017] The first touch-sensitive sensor and the display unit are designed together as a touch-sensitive display unit, specifically a resistive touch-sensitive display unit. The first touch-sensitive sensor utilizes a user interface of the display unit, which is designed as glass or a film. Such touch-sensitive display units are also referred to as touchscreens.

[0018] The two touch-sensitive sensors use different technologies.

[0019] Signals from the two sensors can be evaluated using a suitable evaluation unit, for example, but not exclusively, using an evaluation unit according to DE 102020212536 A1, in order to meet the requirements of a safety application.

[0020] In some configurations, the keypad consists exclusively of keys whose activation is detected by a first touch-sensitive and a second touch-sensitive sensor. Other configurations include additional keys on the keypad.

[0021] In one embodiment, a control device is provided, whereby the function to be performed by pressing the button can be changed, and the display unit associated with the button can be adapted to the function being performed by means of the control device. In other words, it is possible to assign different functions to a button depending on the situation, with a user being visually notified of any changes to the button's function. By adapting the button assignments to the situation, it is possible to minimize the number of buttons in a keypad. However, especially in safety applications, it is essential to prevent accidental button presses. By adapting the display unit's display to the function being performed, intuitive operation and / or display-supported operation are possible. In one embodiment, the function to be performed by pressing the button is also changed by means of the control device.Depending on the application, the control unit is either distributed across different units or designed as a single unit.

[0022] In one embodiment, the keypad includes a selector switch, in particular a rotary dial (also referred to as a rotary switch) or a rotary push-button (also referred to as a rotary / push button), and further in particular an illuminated rotary dial or an illuminated rotary push-button, wherein the selector switch is coupled to the control device, so that the function to be performed by pressing the button can be changed by actuating the selector switch.

[0023] In one embodiment, a selector switch allows the user to select a device and / or component of the safety device, whereby the function to be performed by pressing the button can be changed according to the selected device and / or component. For intuitive user guidance, one embodiment incorporates color coding, whereby different colors can be assigned to different devices and / or components of the safety device. In other embodiments, the selector switch includes an indicator light; for example, the selector switch is designed as an illuminated rotary dial or illuminated rotary push-button, with the control unit configured to color-code the selector switch and the button according to the selected device and / or component.

[0024] In one embodiment, several buttons are provided, and the display assigned to each button on the display unit can be changed according to a menu using the control unit. Depending on the embodiment, all or individual buttons can be assigned functions situationally, so that the number of buttons on the keypad can be reduced and / or a user has access to only a defined selection of functions depending on the situation and / or pre-selection. In some embodiments, the first sensor and / or the second sensor is / are linked to the control unit, so that pressing a button opens or closes a submenu. In one embodiment, the button for opening a submenu is different from the buttons for closing a submenu. In other embodiments, the button assignment for opening and closing can be uniform, at least for certain submenus.In other embodiments, a selector switch is provided as an alternative or additional element. The selector switch is linked to the control unit, allowing a menu to be accessed by pressing the selector switch, in particular a menu assigned to a specific unit and / or component of the safety device. Each of the buttons is assigned a function to be performed according to the menu selected by the selector switch. In one embodiment, color coding is provided, with different colors assigned to different components and / or units of the safety application. When a menu assigned to a component and / or unit is accessed by pressing the selector switch, the selector switch and individual buttons, multiple buttons, or all buttons are color-coded accordingly.

[0025] The touch-sensitive display unit is located below the switch overlay. The switch overlay is preferably designed such that, in the case of multiple buttons, it is possible to identify which button has been pressed.

[0026] In one embodiment, an elastically deformable layer, in particular a silicone layer, is provided, wherein the keycap(s), or in the case of multiple keys, the keycaps, are embedded in the elastically deformable layer and can be adjusted from a rest position to an actuated position against the restoring forces acting upon the elastically deformable layer. In some embodiments, the silicone layer also serves to protect the keypad from dust and water. The restoring forces of the elastically deformable layer are sufficient in some embodiments to return a key designed as a momentary switch to its initial state when contact or applied force is removed. Other embodiments provide additional restoring elements.

[0027] The keypad comprises, in various configurations, a plurality of keys, each with a keycap, wherein a touch of a keycap of the plurality of keys and / or a force input on a keycap of the plurality of keys with a human finger or an input element can be located by means of the first touch-sensitive sensor and / or by means of the second touch-sensitive sensor.

[0028] A second aspect involves creating a control unit for a mobile machine, such as agricultural machinery, construction equipment, a forklift, or similar, comprising a comprehensive keypad. The control unit can be designed to suit the specific application. For example, it can be integrated into a steering wheel, armrest, or dashboard, and / or designed as a portable control unit.

[0029] The ability to adapt the display on the keys to the situation allows the number of keys to be reduced compared to conventional control units, while maintaining intuitive operation.

[0030] A third aspect involves the use of a keypad with a keycap that is at least partially transparent and a display unit located below the keycap in an operating unit for a mobile machine, such as an agricultural machine, a construction machine, or a forklift. The keypad includes two sensors to meet the safety requirements of such mobile machines.

[0031] A function to be performed by pressing a selected key can be visually indicated by designing the display with colors, pictograms assigned to the keys, characters assigned to the keys, or similar means.

[0032] In one embodiment, the use provides that a function to be performed by pressing the button can be changed and a display on the display unit assigned to the button is adapted to the function to be performed.

[0033] In some configurations, the keypad includes several keys, with a display on the display unit assigned to the keys that can be changed according to a menu.

[0034] In some configurations, the device allows one of the buttons to be pressed to open or close a submenu.

[0035] Alternatively or additionally, in certain configurations, the use provides that the function to be performed by pressing the button is changed by actuating a selector switch coupled to the control device, in particular a rotary dial or a rotary push-button, and further, in particular, an illuminated rotary dial or an illuminated rotary push-button. In particular, when using a keypad with multiple buttons, it is provided that a menu intended for a component and / or device is selected by means of the selector switch, whereby selecting the menu assigns a function defined for the component and / or device to one, several, or all buttons of the keypad.For intuitive identification of a selected component and / or device, a color is assigned in one design of the component and / or device, whereby when the component and / or device is selected using the selector switch, the selector switch and one, several or all keys of the keypad are identified by the assigned color. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Further advantages and aspects of the invention will become apparent from the claims and from the description of exemplary embodiments of the invention, which are explained below with reference to the schematic figures. These show: Fig. 1 a keypad in an exploded view and Fig. 2 a control unit arranged on an armrest comprising a keypad in a perspective view. DETAILED DESCRIPTION OF THE EXECUTION EXAMPLES

[0037] Fig. Figure 1 schematically shows an exploded view of a keypad 1 comprising several keys 2, in the illustrated embodiment five keys, each with a keycap 20.

[0038] The touch caps 20 are embedded together in an elastically deformable layer 3 and can be individually adjusted from a rest position to an actuating position against restoring forces acting on the elastically deformable layer 3.

[0039] Viewed in the direction of actuation, below the keycaps 20, a display unit 4, a first touch-sensitive sensor 5, and a second touch-sensitive sensor 6 are provided. The elastically deformable layer 3, the display unit 4, the first touch-sensitive sensor 5, and the second touch-sensitive sensor 6 are arranged in a housing comprising a base 70 and a top plate 71. The top plate 71 has recesses 72 for the keycaps 20, so that the keycaps 20 are accessible for actuation from an outside of the housing. In certain embodiments, the elastically deformable layer is a silicone layer, which also allows the housing to be sealed against the ingress of dust and / or liquids.

[0040] The keycaps 20 are each at least partially, preferably completely, transparent, so that a display on the underlying display unit 4 is visible via the keycaps 20.

[0041] The first touch-sensitive sensor 5 and the second touch-sensitive sensor 6 are arranged such that a touch of one of the keycaps 20 and / or a force input on one of the keycaps 20 with a human finger or an input element can be detected and localized simultaneously by means of the first touch-sensitive sensor 5 and by means of the second touch-sensitive sensor 6, i.e., can be assigned to the corresponding key 2.

[0042] The first touch-sensitive sensor 5 and the display unit 4 are designed together as a touch-sensitive display unit, with one surface of the display unit being used as part of the first touch-sensitive sensor 5.

[0043] The second touch-sensitive sensor 6 is designed as a switching film comprising a separating layer 60 and two conductive layers 61, 62, which are separated in the rest state by means of the separating layer 60.

[0044] The display unit 4, in particular the touch-sensitive display unit, is arranged below the second touch-sensitive sensor 6, which is designed as a switch film, in the direction of actuation. To allow a view of the display unit 6, the switch film is at least partially transparent in some embodiments. In other embodiments, the switch film has cutouts 63 as shown. To actuate the switch film so that the conductive layers 61, 62 touch each other, a plunger (not shown) is provided on the back of each of the keycaps 20 facing the display unit 4 in some embodiments.

[0045] The keypad further includes a schematically depicted control device 8 for controlling the display unit 4.

[0046] In some configurations, a display assigned to the keys 2 on the display unit 4 can be changed by means of the control device 8.

[0047] In certain configurations, it is provided that the control unit 8 allows a function to be performed by pressing button 2 to be changed, whereby the display on the display unit 4 assigned to button 2 is adapted to the function to be performed. By adapting the display to the changed function, the function assigned to button 2 can be easily indicated to the user.

[0048] The control unit 8 and the display unit 4 are designed in such a way that the display on the display unit 4 assigned to the buttons 2 can be changed by means of the control unit 8 according to a menu.

[0049] For example, one embodiment provides that in an initial state a main menu is displayed on the keypad 1, whereby a user can select a submenu by selecting and pressing one of the keys 2. In this embodiment, pressing this key 2 changes the function to be performed by pressing each key 2, according to the selected submenu.

[0050] The display assigned to keys 2 on the display unit 4 can be changed by means of the control device 8 according to the selected submenu.

[0051] In one embodiment, it is provided that when a submenu is selected, the display on the display unit 4 assigned to a defined button 2 can be changed by means of the control device 8 so that it can be recognized as button 2 for closing the submenu or returning to a main menu.

[0052] Keypad 1 can be integrated into a control unit for a mobile machine, such as an agricultural machine, a construction machine, a forklift truck, or the like.

[0053] In various configurations, the keypad 1 is integrated, for example, into a control unit for a mobile machine, such as an agricultural machine, a construction machine, a forklift truck, or the like, with several components. A component can be selected from a main menu by pressing its corresponding button 2. Within this main menu, the display unit 4 can be controlled such that a corresponding pictogram and / or a defined color is displayed for each component assigned to buttons 2. Pressing one of the buttons 2, and thus selecting the assigned component, opens a submenu. This submenu modifies all or some of the functions that can be performed using the buttons 2, and the display on the display unit 4, corresponding to the buttons 2, is changed by the control unit 8 according to the selected submenu.

[0054] Fig. Figure 2 shows a schematic perspective view of a control unit 90 arranged on an armrest 9, comprising two joysticks 92, a direction switch 93 and a keypad 1 with three buttons 20. The armrest 9 with the control unit 90 can be used, for example, on a mobile machine such as an agricultural or construction machine, a forklift truck and in numerous industrial applications.

[0055] However, the invention is not limited to the use of a keypad 1 of a control unit 90 arranged on an armrest 9. Rather, numerous other applications are conceivable.

[0056] The in Fig. The keypad 1 shown comprises three keys 2 and a selector switch 80, designed, for example, as a rotary push-button. The selector switch 80 is equipped with a Fig. 2 control unit not shown 8 (see Fig. 1) is coupled so that by actuating the selector switch 80 the function to be performed by pressing one, several or all keys 2 can be changed.

[0057] The in Fig. The control unit 90 shown in section 2 serves, for example, to operate a mobile machine, such as an agricultural machine, a construction machine, a forklift, or the like, with several components. Using the selector switch 80, a main menu, a submenu for one of the components, and / or a submenu for another machine feature, such as an air conditioning unit, can be selected in various configurations. Depending on the configuration and / or menu, selecting a menu changes all or some of the functions that can be performed using the buttons 2, whereby the display on the display unit 4, corresponding to the buttons 2, is changed by the control unit 8 according to the selected menu.

Claims

[1] Keypad for an operating unit of a safety application comprising at least one key (2) with a keycap (20), a first touch-sensitive sensor (5) and a second touch-sensitive sensor (6), wherein the first touch-sensitive sensor (5) and the second touch-sensitive sensor (6) are arranged such that a touch of the keycap (20) and / or a force applied to the keycap (20) with a human finger or an input element can be detected simultaneously by means of the first touch-sensitive sensor (5) and by means of the second touch-sensitive sensor (6), characterized by, that the keycap (20) is at least partially transparent and a display unit is arranged below the keycap (20), wherein the first touch-sensitive sensor (5) and the display unit (4) are designed together as a touch-sensitive display unit, the second touch-sensitive sensor (6) is designed as a switch film comprising a separating layer (60) and two conductive layers (61, 62) separated in the rest state by means of the separating layer (60), and the touch-sensitive display unit is arranged below the switch film. [2] Keypad according to claim 1, characterized by , that a control device (8) is provided, wherein a function to be performed by pressing the button (2) can be changed and by means of the control device (8) a display on the display unit (4) assigned to the button (2) can be adapted to the function to be performed. [3] Keypad according to claim 2, characterized by, that a selector switch (80) is provided, in particular a rotary dial or a rotary push-button, further in particular an illuminated rotary dial or an illuminated rotary push-button, wherein the selector switch (80) is coupled to the control device (8) so that the function to be carried out by pressing the button (2) can be changed by actuating the selector switch (80). [4] Keypad according to claim 2 or 3, characterized by , that several buttons (2) are provided, wherein the display on the display unit (4) assigned to the buttons (2) can be changed according to a menu by means of the control device (8), wherein in particular the first touch-sensitive sensor (5) and / or the second touch-sensitive sensor (6) is / are coupled to the control device (8), so that by pressing one of the buttons (2) it is possible to call up or close a submenu. [5] Keypad according to any one of claims 1 to 4, characterized bythat the touch-sensitive display unit is designed as a resistive touch-sensitive display unit. [6] Keypad according to any one of claims 1 to 5, characterized by , that the two conductive layers (61, 62) of the switch foil are designed as two carbon layers, layers with conductive paste, metallized layers and / or metal layers. [7] Keypad according to any one of claims 1 to 6, characterized by , that an elastically deformable layer (3), in particular a silicone layer, is provided, wherein the touch cap (20) is embedded in the elastically deformable layer (3) and is adjustable from a rest position to an actuating position against restoring forces acting on the elastically deformable layer (3). [8] Keypad according to any one of claims 1 to 7, characterized by, that a plurality of keys (2) are provided, each with a keycap (20), wherein a touch of a keycap (20) of the plurality of keys and / or a force input on a keycap (20) of the plurality of keys with a human finger or an input element can be located by means of the first touch-sensitive sensor (5) and / or by means of the second sensor (6). [9] Control unit for a mobile machine, such as an agricultural machine, a construction machine, a forklift truck, comprising a keypad according to any one of claims 1 to 8. [10] Use of a keypad according to any one of claims 1 to 8 in an operating unit for a mobile machine, such as an agricultural machine, a construction machine, a forklift truck. [11] Use of a keypad according to claim 10, characterized by, that a function to be performed by pressing button (2) can be changed and a display on the display unit (4) assigned to button (2) is adapted to the function to be performed. [12] Use of a keypad according to claim 10 or 11, characterized by , that by actuating a selector switch (80), in particular a rotary dial or a rotary push-button, further in particular an illuminated rotary dial or an illuminated rotary push-button, which is coupled to the control device (8), the function to be carried out by pressing the button (2) is changed.

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