Capacitive sensor and operating element with integrated illumination

Abstract

The invention relates to a capacitive sensor (1) with integrated illumination for an operating element, comprising a carrier plate (10) and a sensor element (20) which is slidably mounted on the carrier plate, the sensor element (20) having a connecting part (21) which is mounted on the carrier plate (10) and an actuating part (22) which can be slid relative to the carrier plate (10) in a predetermined actuating direction (R), the actuation part (22) has an actuation surface (24) for receiving a force (K) acting in an actuation direction (R), and wherein the capacitive sensor (1) further comprises a measuring electrode (30), which is arranged on the carrier plate (10), for detecting a sliding of the actuation part (22) and for determining a force (K) acting on the actuation part (22) and causing a sliding, the capacitive sensor (1) has a lighting element (40) which is arranged on the carrier plate (10) and which is designed to emit light in the actuation direction (R), and wherein the actuation part (22) has a recess (25) through which the lighting element (40) extends and / or through which the light can be emitted in the actuation direction (R) by means of the lighting element (40).

Description

[0001] The invention relates to a capacitive sensor or capacitive force sensor with integrated lighting, and to a control element with such a capacitive sensor and integrated lighting.

[0002] A plurality of operating elements and capacitively operated sensors are known from the prior art as operating elements. If the actuation surface of an operating element is to be illuminated, as is often required in motor vehicles, it is currently common to provide the lighting element separately from the sensor or adjacent to the sensor on a common carrier.

[0003] Since the lighting element is therefore either arranged as its own functional unit completely independently of the sensor or arranged adjacent to the sensor on a common carrier, the installation space requirement of the assembly formed thereby and the complexity of the assembly formed in this way are increased.

[0004] It is therefore an object of the present invention to overcome the above-mentioned disadvantages and to provide a capacitive sensor or a control element having such a sensor which can be illuminated with little need for structural space.

[0005] This object is achieved by the combination of features according to the main claim and the dependent claims.

[0006] Therefore, according to the invention, a capacitive sensor with integrated illumination for an operating element is proposed, which is in particular a capacitive force sensor. According to the invention, the sensor has a carrier plate and a sensor element slidably supported on the carrier plate and a measuring electrode. The sensor element has a connecting portion supported on the carrier plate and an actuating portion slidable relative to the carrier plate in a predetermined actuation direction. In this case, the connecting portion is preferably stationary relative to the carrier plate, in particular fixed to the carrier plate, while the actuating portion can be movable or slidable, for example, parallel to the carrier plate, in particular orthogonal to the carrier plate. In this case, the actuating portion has an actuating surface for receiving a force acting in the actuation direction, in particular a force applied by a force transmission element, which force can also be referred to as an actuating force. As mentioned above, the sensor also includes a measuring electrode arranged on the carrier plate for detecting the sliding of the actuating portion and for determining the force acting on the actuating portion and causing the sliding. According to the invention, the capacitive sensor has an illumination element arranged on the carrier plate, which is preferably arranged on a common side of the carrier plate together with the sensor element and / or fixed to the carrier plate. The lighting element, in particular an LED, and further in particular a top-emitting LED, is also configured to emit light in the actuation direction, wherein this can be guided to the illuminable field in the actuation direction directly or, for example, via a light guide element, as will be explained further below. In order to achieve a compact construction, it is also provided that the actuation part has a recess, which is in particular arranged in the center or middle of the actuation part, through which recess the lighting element extends and / or through which light can be emitted by the lighting element in the actuation direction, so that the lighting element can be arranged in a partial surface defined by the actuation part or, typically, by the sensor element on a surface of the carrier plate.

[0007] The required construction space is thus significantly reduced or optimized, since the illumination element can be arranged integrally in the area occupied by the sensor element instead of adjacent to the sensor.

[0008] Although only one lighting element is mentioned, according to the present invention, a plurality of lighting elements or lighting elements configured to emit light of different colors may also be arranged to pass through the groove and / or emit light passing through the groove.

[0009] In this case, an advantageous variant provides that the carrier plate has a first side, on which the sensor element is arranged and / or fixed, on which the connecting part of the sensor element supports and on which the lighting element is fixed. Furthermore, the carrier plate can have a second side, which is preferably opposite the first side, and on which the measuring electrode is arranged and / or fixed opposite the sensor element and the lighting element. Thus, the sensor element, the lighting device and the measuring electrode are preferably superimposed on the carrier plate in a top view, wherein the area required for the component is determined only by the sensor element and / or the measuring electrode and not by the lighting device.

[0010] Preferably, the connection part and / or the mounting part of the carrier plate explained further below is defined or limited on a surface, i.e. on a first side of the carrier plate, at least in sections, in particular completely defines the partial surface on or in which the lighting element is arranged and / or fixed. To this end, the connection part can, for example, run around the partial surface in an annular manner or generally in a closed contour. Alternatively, however, the connection part can also have other shapes and, for example, can also be formed from two or more parts, which can, in particular, be evenly distributed around the partial surface.

[0011] In addition to the connecting part and the actuating part, the sensor element can also have at least one spring part, which is connected to the connecting part and the actuating part by means of the spring part that allows and determines the sliding. The force required for sliding or sliding and the sliding path along which the actuating part of the sensor element can slide by the actuating force can be determined in particular by the shape of the at least one spring part. If the force is introduced into the sensor element via the actuating part or the actuating surface, the sensor element can be supported on the carrier plate via the connecting part and a spring force that counteracts the actuating force is provided via at least one spring part, thereby determining the sliding of the actuating part. The sliding of the actuating part in turn leads to a change in the electric field that can be provided by the measuring electrode, which in turn can be detected at the measuring electrode and can therefore be evaluated, so that the sliding and the actuating force that causes the sliding can be determined based on the change in the electric field.

[0012] Preferably, the connecting part at least sections and in particular completely surrounds the actuating part, in particular in a top view onto the carrier plate.

[0013] This applies to the sensor element, which is in particular of one-piece design and is preferably a punched and bent part.

[0014] The carrier plate can be a layer of a printed circuit board or a multilayer printed circuit board. Furthermore, the carrier plate can be of rigid or flexible construction. Furthermore, an advantageous design provides that the carrier plate has a mounting section, which is in particular configured as a soldering surface, for fixing or surface mounting of connecting sections of the sensor element, i.e. for fixing the sensor element to the carrier plate. Furthermore, printed tracks for electrical contacting of the sensor element and / or sensor electrodes and / or lighting elements can be arranged, constructed and / or integrated into the carrier plate, for example by printing or etching technology and for example by multilayer, thin-film or thick-layer technology.

[0015] The measuring electrode is preferably a coil body, which is arranged on a carrier plate or, in the case of a multilayer printed circuit board, can be arranged between two layers. The coil body can also be formed, for example, by a printed track produced by printing or etching technology, which can be directly integrated into a layer or printed circuit board accordingly.

[0016] In particular, in order to supply power or control each connection of the lighting element, the lighting element requires a printed track for contacting the corresponding connection. In the case of a simple lighting element with two connections, two printed tracks are required accordingly.

[0017] A printed track for contacting the lighting element can extend from outside a defined partial surface into the partial surface, or allow an electrical connection to a lighting element arranged within the partial surface. To this end, for example, a first printed track can be provided that is integrally formed with the mounting part of the sensor element, so that the printed track does not have to bypass the mounting part and results in a simple structure.

[0018] The printed track or the second printed track can, for example, be constructed in two parts and extend in each case together with both parts to the assembly part, wherein, in order to bridge the assembly part, the two parts can be connected to one another, for example by bonding, i.e. by means of a wire or by means of a carrier board, in particular by means of a printed track section formed within the carrier board, on the back side of the carrier board or, in the case of a multilayer printed circuit board, on another layer of the printed circuit board.

[0019] However, all or both printed tracks for contacting the lighting element or its connections can also extend through the carrier board and be located on a second side of the carrier board facing away from the first side, or in the case of a multilayer printed circuit board, in another layer of the printed circuit board or lead to control electronics.

[0020] According to an advantageous design, the actuating part can be configured as a substantially flat body, which can have, for example, a rectangular, square, circular or elliptical outer contour, i.e. a contour in a top view. In this case, a sliding of such a body can be detected by the measuring electrodes or can influence the electric field provided by the measuring electrodes in a measurable manner.

[0021] Furthermore, in the non-actuated state, the actuation part can be spaced apart from the carrier plate and / or the connecting part in the actuation direction, wherein, in contrast to the actuated state, the actuation part is not subjected to an actuation force and can therefore slide according to the distance to the connecting part or the carrier plate during actuation. This distance preferably determines the maximum sliding path, which distance can additionally or alternatively be smaller than the overall height of the lighting element, so that the lighting element passes through the actuation part through the recess both in the actuated and non-actuated state.

[0022] Furthermore, the actuating part or the entire sensor element can be configured as a chuck in order to simultaneously provide a tactile feedback to the operator during actuation, ie under the action of a force.

[0023] In this case, an advantageous variant of the capacitive sensor provides that the recess is, for example, a substantially oval, circular or angular hole, with a closed contour, or generally with a closed contour. Additionally or alternatively, the shape of the recess can correspond to the outer contour of the lighting element, i.e., have a contour corresponding to or slightly larger than the outer contour of the lighting element, so that the area provided by the actuating part is minimized only by the recess, and the influence of the electric field by the recess is therefore only minimally changed. For example, the dimensions of the recess are selected in such a way that during the intended movement or sliding of the actuating part, no contact occurs between the lighting element and the actuating part. The actuating surface, to which the actuating force can be applied, preferably directly adjoins the recess.

[0024] In order to be able to provide a compact assembly and simplified control, according to another advantageous variant, the capacitive sensor has control electronics, which are arranged on the carrier plate and / or are in contact with the measuring electrodes via signal technology and are configured to determine the force acting on the actuating part and causing the sliding as a function of the sliding of the actuating part detected by the measuring electrodes. Furthermore, the control electronics can additionally or alternatively be configured to control the lighting element as a function of an external control signal and / or as a function of the sliding of the actuating part and / or the force acting on the actuating part. In order to determine the sliding and / or the force, the properties of the sensor element can be stored in the control electronics or the properties of the sensor element can be called up from the control electronics.

[0025] With regard to the actuation of the lighting element, the control electronics may for example be configured to actuate the lighting element in such a way that, for example, light is emitted for a predetermined time in the case of a certain force or a certain sliding movement, so that no external actuation is required.

[0026] Additionally or alternatively, however, external control signals can be used to actuate the lighting element, which can be transmitted to the control electronics, for example, via control contacts provided for this purpose or via a bus. Such control contacts for actuating the lighting element can be integrated into a common connection of the sensor, for example, together with other contacts for supplying power to the sensor and / or for transmitting a sliding movement and / or a force detected or determined by the control electronics.

[0027] Another aspect of the invention relates to an operating element having a capacitive sensor according to the invention. The operating element has a button for receiving a force that can be applied by an operator, the button having an illuminable field. In addition, the operating element has a force transmission element that rests on an actuation surface of the sensor element and is configured to transmit the force that can be applied by the operator to the button from the button to the sensor element.

[0028] In this case, an advantageous development of the operating element provides that a light guide covering the recess of the actuating part is arranged in the force transmission element and is configured to guide the light emitted by the lighting element to the illuminable field. Alternatively, the force transmission element can be configured as a whole as a light guide covering the recess of the actuating part and is configured to guide the light emitted by the lighting element to the illuminable field.

[0029] Furthermore, the illuminable field and / or in particular the entire button can be designed as a diffuser and / or a diffuser can be arranged between the lighting element and the button such that light is scattered at the diffuser.

[0030] Furthermore, the illuminable field or diffuser may have the form of a symbol or pictogram, or may be configured as such.

[0031] The features disclosed above can be combined as desired, as long as this is technically possible and the features do not contradict one another.

[0032] Further advantageous developments of the invention are characterized in the dependent claims and are described in more detail below together with the description of preferred embodiments of the invention in conjunction with the accompanying drawings. In the drawings:

[0033] Figure 1 A partial cross section of a capacitive sensor is shown;

[0034] Figure 2 shows a sensor element of a capacitive sensor;

[0035] Figure 3 shows a top view of a carrier plate of a capacitive sensor;

[0036] Figure 4 shows a side cross-sectional view of the operating element in a non-actuated state;

[0037] Figure 5 A side sectional view of the operating element is shown in an actuated state.

[0038] The accompanying drawings are schematic examples. The same reference numerals in the accompanying drawings represent the same functions and / or structural features.

[0039] Figure 1 A partial cross section of a capacitive sensor 1 is shown, wherein a sensor element 20 is fixed on a first side 11 of a carrier plate 10 on a mounting portion 14, which is configured as a welding surface, and a measuring electrode 30 is arranged on an opposite second side 12 of the carrier plate 10, the measuring electrode 30 being configured to provide an electric field and to detect changes in the electric field via the sensor element 20.

[0040] The sensor element 20 has a connecting portion 21 fixed to the mounting portion 14, an actuating portion 22, and a plurality of spring portions 23 connecting the connecting portion 21 to the actuating portion 22, which allow the movability or slidability of the actuating portion 22 relative to the connecting portion 21. In addition, the spring portion 23 provides a spring force as a reaction force to a force K acting on the actuating surface 24 in the actuating direction R, so that the spring portion 23 preferably determines the force K required for a specific sliding of the actuating portion 22 along the actuating direction R together with the actuating portion 22.

[0041] In this case, the carrier plate 10 also forms a layer 10 of a multilayer printed circuit board with a further layer 82 , so that the measuring electrode 30 is sandwiched between the layers 10 , 82 and is protected.

[0042] According to the proposed structure, the connecting portion 21 or the mounting portion 14 of the sensor element 20 defines a partial surface 13 with the surrounding surface 11 on the first side 11 or the surface 11 of the carrier plate 10, respectively, wherein the actuating portion 22 is movably held near the partial surface 13, and the lighting element 40 is fixed to the carrier plate 10 in the partial surface 13 so that the lighting element 40 can emit light in or along the actuating direction R. The actuating portion 22 forms a groove 25, and in a top view, the lighting element 40 is arranged in the groove 25 so that light emitted by the lighting element 40 can be emitted through the groove 25.

[0043] If an area and, for example, a button 60 is now to be illuminated, the lighting device no longer needs to be arranged on the adjacent surface 11 of the carrier plate 10, but rather outside the partial surface 13 and can be directly integrated into the capacitive sensor 1 and reduce the structural space accordingly, or be fixed to the area defined by the sensor element 20 on the carrier plate 10.

[0044] exist Figure 2 For example, according to Figure 1 The sensor element 20 used in the capacitive sensor 1 is shown in a top view, i.e. in a view along the actuation direction R. The present sensor element differs from similar or known sensor elements in that, as shown in the figure, a recess 25 is provided in the actuation part 22, which in this case has a circular closed contour, so that the lighting element 40 can be arranged in this contour or recess 25 and light can pass through the actuation part 22.

[0045] The actuation surface 24 for receiving the force K acting in the actuation direction R extends radially inwards until directly reaching the groove 25 so that the force K can be further transferred to the sensor element 20 via the largest possible surface and leads to sliding of the actuation part 22 .

[0046] Figure 3The carrier plate 10 is shown in a top view, wherein the structure shown or according to Figure 3 The features can also be used for Figure 1 The capacitive sensor 1 is shown.

[0047] Importantly, a fitting portion 14 corresponding to the connection portion 21 is formed on the first side 11 or surface 11 of the carrier plate 10, which separates the partial surface 13 of the surface 11 from the surrounding area. As shown in the figure, the partial surface 13 can be completely defined, or it can also have a connection with the surrounding area in sections.

[0048] Within the part surface 13, a lighting element 40 is fixed to the carrier board 10 and is in electrical contact with two printed tracks 15, 16 for operating the lighting element 40. The first printed track 15 is formed integrally with the mounting section 14, so that the lighting element 40 is in electrical contact with the control electronics 50 arranged on the carrier board 10 via the first printed track 15 and the mounting section 14. The second printed track 16 comprises two parts, wherein a first part is in contact with the lighting element 40 within the part surface 13 and a second part is in contact with the control electronics 50 outside the part surface 13. The two parts of the second printed track 16 again bridge the mounting section 14 and are connected to each other, for example in another layer of a printed circuit board comprising the carrier board 10 or by wire bonding.

[0049] In principle, of course, the two printing tracks 15 , 16 can also be formed according to the second printing track 16 or can be led out of the partial surface 13 on the second side 12 .

[0050] Figure 4 and Figure 5 Shows that according to Figure 1 An operating element 2 of a capacitive sensor 1, wherein Figure 4 The operating element 2 or the sensor 1 is shown in a non-actuated state, in which no force K acts on the sensor element 20 of the sensor 1 . Figure 5 The operating element 2 or the sensor 1 is shown in an actuated state, in which a force K which can be applied by an operator acts on the sensor element 20 of the sensor 1 .

[0051] The operating element 2 comprises in particular a push button 60 with an illuminable field 61 and a force transmission element 70 which is arranged between the push button 60 and the sensor element 20 and which bears against the actuation surface 24 of the actuation section 22 .

[0052] because Figure 4 The button 60 is not subjected to a pressure or force K, and the actuation portion 22 has a first distance A1 from the surface 11 or first side 11 of the carrier plate 10, so that the electric field provided by the measuring electrode 30 is in a first state or is substantially unaffected.

[0053] If the operator then applies a force K or pressure on the button 60, the force K is transmitted via the force transmission element 70 to the actuation surface 24 or the actuation part 22, as a result of which the actuation surface 24 or the actuation part 22 slides in the actuation direction R towards the surface 11 or the first side 11 of the carrier plate 10, so that the first distance A1 decreases towards the second distance A2, and the electric field is affected, which can be detected by the measuring electrodes 30 and in particular evaluated by the control electronics 50 to determine the force K and / or the sliding. Accordingly, the sliding is a change from the first distance A1 to the second distance A2.

[0054] In this case, the control electronics 50 can not only evaluate the signal transmitted by the measuring electrode 30 to determine the sliding and the force K causing the sliding. For example, the lighting element 40 can also be controlled by the control electronics 50, whereby the control of the lighting element 40 by the control electronics 50 can be based on the external control signal and / or the sliding of the actuating part 22 or the force K acting on the actuating part 22. For example, if the lighting element 40 is controlled to emit light L, the external control signal can be omitted as long as the force K exceeds a predetermined limit value, as a result of which the control of the operating element 2 is significantly simplified.

Claims

1. A capacitive sensor (1) with integrated lighting for an operating element, comprising: A carrier plate (10) and a sensor element (20) slidably supported on the carrier plate, in, The sensor element (20) has a connection portion (21) supported on the carrier plate (10) and an actuation portion (22) slidable relative to the carrier plate (10) along a predetermined actuation direction (R), wherein the actuation portion (22) has an actuation surface (24) for receiving a force (K) acting in an actuation direction (R), And wherein the capacitive sensor (1) further comprises a measuring electrode (30) arranged on the carrier plate (10) for detecting the sliding of the actuating part (22) and for determining the force (K) acting on the actuating part (22) and causing the sliding, It is characterized in that The capacitive sensor (1) has a lighting element (40) arranged on the carrier plate (10) and configured to emit light in the actuation direction (R), The actuation portion (22) has a groove (25), the lighting element (40) extends through the groove (25) and / or light can be emitted through the lighting element (40) in the actuation direction (R) through the groove (25).

2. The capacitive sensor according to claim 1, in, The carrier plate (10) has a first side (11), on which the sensor element (20) is arranged and / or fixed, and on which the connecting part (21) of the sensor element (20) supports and the lighting element (40) is fixed. And / or wherein the carrier plate has a second side (22), on which the measuring electrode (30) is arranged opposite the sensor element (20) and the lighting element (40) and / or is fixed.

3. The capacitive sensor according to claim 1 or 2, in, The connecting portion (21) defines a partial surface (13) at least in sections on the surface (11) of the carrier plate (10), and the lighting element (40) is arranged and / or fixed on the partial surface (13).

4. Capacitive sensor according to any one of the preceding claims, in, The connecting part (21) is connected to the actuating part (22) via at least one spring part (23) which allows and determines sliding. And / or wherein the connecting portion (21) at least partially runs around the actuating portion (22).

5. Capacitive sensor according to any one of the preceding claims, in, The carrier plate (10) is a layer of a printed circuit board or a multi-layer printed circuit board, and / or wherein the carrier plate (10) is of rigid or flexible construction, and / or wherein the carrier plate (10) has a mounting portion (14) for fixing the connecting portion (21) to the carrier plate (10), And / or wherein printed tracks for electrical contacting the sensor element (20) of the sensor electrode (30) and / or the lighting element (40) are arranged, formed on the carrier plate (10) and / or integrated into the carrier plate (10).

6. Capacitive sensor according to any one of the preceding claims, in, The actuating part (22) is configured as a planar body, the sliding movement of which can be detected by the measuring electrode (30) and / or in a non-actuated state, spaced apart from the carrier plate (10) and / or the connecting portion (21) in the actuation direction (R).

7. Capacitive sensor according to any one of the preceding claims, in, The groove (25) is a hole with a closed contour. and / or wherein the shape of the groove (25) corresponds to the outer contour of the lighting element (40), so that the area provided by the actuating portion (22) is minimized by the groove (40) And / or wherein the actuation surface (24) is directly adjacent to the groove (25).

8. Capacitive sensor according to any one of the preceding claims, It comprises control electronics (50) which are arranged on the carrier plate (10) and / or are in contact with the measuring electrode (30) via signal technology and are designed to: determining a force (K) acting on the actuating part (22) and causing the sliding movement based on the sliding movement of the actuating part (22) detected by the measuring electrode (30), And / or the lighting element (40) is operated according to an external control signal and / or a sliding movement and / or a force (K).

9. An operating element (2) comprising a capacitive sensor (1) according to any one of the preceding claims, It comprises a button (60) for receiving a force (K) which can be applied by an operator, the button having an illuminable field (61), and a force transmission element (70) which abuts the actuation surface (24) of the sensor element (20) and is configured to transmit the force (K) from the button (60) to the sensor element (20).

10. An operating element according to the preceding claim, in, A light guide covering the groove (25) is arranged in the force transmission element (70), the light guide being configured to guide light emitted from the lighting element (40) to the illuminable field (61), Or wherein the force transmission element (70) is integrally configured as a light guide covering the groove (25), and the light guide is configured to guide light emitted from the lighting element (40) to the illuminable field (61).

11. An operating element according to any one of the two preceding claims, in, The illuminable field (61) and / or the button (60) are configured as diffusers and / or a diffuser is arranged between the lighting element (40) and the button (60).

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