Capacitive operating unit

Abstract

The invention relates to a capacitive operating unit (1) for a motor vehicle, comprising a capacitive sensor element (30), a switching arrangement (10) and a cover element (20) for hermetically separating the sensor element (30) from the switching arrangement (10), on the visible side (21) of which the switching arrangement (10) is arranged and on the opposite rear side (23) of which the capacitive sensor element (30) is arranged, wherein the switching arrangement (10) has a coupling electrode (11) coupled to an electric field generated by the sensor element (30), at least one switching element (40) and, for each switching element (40), a sensor electrode (12) assigned to a predetermined position (13, 14), which are electrically connected to the coupling electrode (11) by means of electrical conductors (15) via the respective switching element (40) such that, when the respective switching element (40) is actuated at the respective predetermined position (13, 14), the at least one sensor electrode (12) can cause a change in the electric field that can be captured by the sensor element (30), wherein the switching arrangement (10) has an electrically non-conductive operating element (50) which can be actuated by the operator and which is designed to act on at least one of the switching elements (40) in a directly switching manner when actuated.

Description

[0001] Capacitive control unit

[0002] Description:

[0003] The invention relates to a capacitive operating unit for a motor vehicle and in particular for a seat of a motor vehicle.

[0004] A wide variety of operating units, including operating units based on capacitive sensing, are known from the prior art. For example, DE 20 2022 103 370 U1 proposes a capacitive operating unit in which an operating element is separated from a sensor for detecting an operating input introduced via the operating element, so that the sensor element can be provided completely independent of the operating element on the one hand and invisible to the operator on the other. In this operating unit, the operating element movable by the operator must be made of an electrically conductive material or must at least contain an electrically conductive contact. This means that the production of the operating element is comparatively cost-intensive and is also subject to design restrictions, since the operating element itself may not be directly touched by the operator in some cases.

[0005] The invention is therefore based on the object of overcoming the aforementioned disadvantages and providing a capacitive operating unit which is simple and cost-effective to manufacture, in which the sensor element and the operating element are still separated from one another.

[0006] This problem is solved by the combination of features according to patent claim 1.

[0007] According to the invention, a capacitive operating unit for a motor vehicle is therefore proposed, which is, for example, an operating unit for adjusting a vehicle seat. The operating unit has a capacitive sensor element, a switching arrangement and a cover element for separating the sensor element from the switching arrangement. The sensor element is designed to generate an electric field and, in parallel, to detect a change in the generated electric field, ie, in particular, also a position of such a change in the electric field. The switching arrangement is designed, when actuated by an operator, to bring about the change in the electric field, which can be detected accordingly by the sensor element together with the position of the change.The switching arrangement is arranged on a closed, visible side facing the operator during intended use, and the sensor element is arranged on a closed, rear side facing away from the operator during intended use, opposite the visible side, and also closed. Such that the switching arrangement and the operating element do not touch each other and are arranged independently of each other on the cover element, which is preferably formed in a single plane or as a cover plate. Furthermore, the cover element can also be designed to opaquely and / or hermetically separate the sensor element and the operating element from each other.The switching arrangement also has a coupling electrode coupled to the electric field, at least one switching element and, for each switching element, a sensor electrode assigned to a predetermined position, which are electrically connected to the coupling electrode via the respective switching element by electrical conductors, so that when the respective switching element is actuated at the respective predetermined position, a change in the electric field that can be detected by the sensor element can be brought about by the at least one sensor electrode, so that the change detected by the sensor element at the predetermined position can be determined whether the at least one switching element has been actuated and which switching element has been actuated.The switching arrangement further comprises an operator-operable, electrically non-conductive, and preferably completely electrically non-conductive operating element, which is designed to actuate at least one of the switching elements directly upon actuation. Accordingly, the sensor element can discriminately detect the actuation of the switching elements through the respectively assigned and predetermined positions and transmit this information, for example, to a control unit, which can control actuators assigned to the respective switching elements or trigger functions.

[0008] Such an inventive design offers numerous advantages. For example, a cost-effective material can be selected for the control element, which also simplifies its production. Furthermore, the control element is subject to fewer design restrictions and can therefore be customized. This also enables smaller, i.e., less space-intensive, control elements.

[0009] It is also advantageous that the positions at which a change in the electric field is to be induced by the sensor electrodes can be flexibly adapted to the intended use and therefore do not have to be fixed. Furthermore, the exact positioning of the switching arrangement relative to the sensor element is irrelevant, as long as the electric field of the sensor element can be coupled into the switching arrangement via the coupling electrode and output via the at least one sensor electrode in a detectable manner for the sensor element. Various variants of switching arrangements can also be provided, which can be provided alternatively to one another on the cover element and interacting with the sensor element.

[0010] Furthermore, the capacitive operating unit can have two or more switching arrangements instead of one switching arrangement, which are all provided on the sensor element, so that the electric field can be coupled into the switching arrangements and changes in the electric field can be detected by the sensor element through the switching arrangements.

[0011] If various switching arrangements or multiple switching arrangements can be arranged on the cover element, the sensor element or a control unit connected to it can be configured to detect the type and / or number of switching elements. For this purpose, for example, the relative arrangement of the positions at which a change in the electric field is detectable or is detected can be compared with stored position data.

[0012] Preferably, the operating element on the visible side of the cover element can be deflected by the operator around a neutral, ie operation-free, central position in a predetermined number of actuation directions, wherein each actuation direction is further preferably assigned exactly one switching element.

[0013] An advantageous variant provides that the switching arrangement has a base plate fixed to the visible side of the cover element, for example, by gluing or another non-damaging fastening method for the cover element, on which the sensor electrodes are arranged or on which at least one sensor electrode is arranged. The base plate is preferably made of an electrically non-conductive material, with the sensor electrodes being arranged, for example, on a surface of the base plate facing the visible side of the cover element.

[0014] Furthermore, the coupling electrode can be designed as an electrically conductive frame surrounding the base plate and the sensor electrodes on the cover element. Alternatively, the coupling electrode can be designed separately from the frame and arranged accordingly on a frame surrounding the base plate and the sensor electrodes on the cover element, which frame itself can be made of an electrically non-conductive material. Furthermore, multiple coupling electrodes can also be provided.

[0015] The operating element can be designed, for example, by means of a dome or projection extending parallel to a visible surface of the cover element, to actuate the at least one switching element in a translational movement relative to the visible surface of the cover element.

[0016] Preferably, the at least one switching element has an electrically conductive contact body for establishing the electrical connection between the coupling electrode and the respective sensor electrode, which can be acted upon by the operating element directly or indirectly via a housing of the switching element.

[0017] If a housing is provided, this and preferably the entire switching element with the exception of the contact body and contacts for contacting it can be made of an electrically non-conductive material.

[0018] Furthermore, the switching arrangement preferably has a central support extending orthogonally to the cover element, on which the at least one switching element is held so as to be operable along a switching path running parallel to the visible side of the cover element.

[0019] According to an advantageous further development, the switching arrangement also has at least two switching elements which are arranged opposite one another in pairs and can be actuated in opposite directions.

[0020] Furthermore, the control element can be designed in one piece.

[0021] The operating element can also be deflectably fixed to the aforementioned frame, the center support, or directly to the visible surface of the cover element. It can preferably be spring-returned to the neutral center position and, in particular, guided so as to be deflectable along predetermined actuation paths or directions. Furthermore, the operating element can be formed entirely from an elastically deformable material, so that the spring return and the spring-loaded mounting are provided by the operating element or its elastic material itself.

[0022] Spring elements can be provided for such a spring return. Alternatively, the spring return can also be formed integrally by the switching elements, which can thus be designed integrally as spring elements for returning the operating element to the neutral center position. For this purpose, it is preferably provided that the switching elements are spring-returned to a non-actuated home position, wherein the operating element is connected to the housing of a respective switching element in such a way that the operating element is simultaneously spring-returned to the neutral center position by a spring return of the switching elements to a non-actuated home position.

[0023] An outer side of the control element facing away from the at least one switching element is also preferably designed directly as a gripping surface for interaction with the operator, wherein the switching element or its outer side can be designed accordingly ergonomically and, for example, to mimic an element to be operated. Thus, a control element for seat adjustment can, for example, be modeled in its shape on the section of the seat to be adjusted by the control element, i.e., in particular, the seat surface or the backrest.

[0024] The preferably opaque cover element, which can also be referred to as a trim or decorative part, preferably also forms a visible surface directly on its visible side. Alternatively, a decorative layer that essentially completely covers the visible side can also be provided on the visible side of the cover element.

[0025] The sensor element is preferably a capacitive touch foil extending flatly on the back of the cover element, which has corresponding connections and can be connected via these and in particular via flexible conductor tracks or a flexible printed circuit board, for example, to the control unit already mentioned.

[0026] The base plate and center support can be formed integrally with each other or independently of each other, and each can be a rigid circuit carrier. If the electrical conductors run over the circuit carrier(s), they are preferably provided as conductor tracks on the respective circuit carrier. The sensor electrodes can also be formed on the base plate, for example, as printed conductor tracks.

[0027] The features disclosed above can be combined as desired, as long as this is technically possible and they do not contradict each other.

[0028] Other advantageous developments of the invention are characterized in the subclaims or are presented in more detail below, together with the description of the preferred embodiment of the invention, with reference to the figures. They show:

[0029] Fig. 1 a capacitive control unit with a control element in neutral middle position;

[0030] Fig. 2 the capacitive control element in an actuated position.

[0031] The figures are schematic examples, with Figure 1 showing an operating unit 1 in a neutral central position and Figure 2 showing an actuated position. Identical reference numerals in the figures indicate identical functional and / or structural features.

[0032] According to the invention, the capacitive operating unit 1 essentially comprises a capacitive sensor element 30, a switching arrangement 10, and a cover element 20 separating them from one another. The sensor element 30 is arranged and fixed on a rear side 23 or a rear surface of the cover element 20, and the switching arrangement 10 is arranged and fixed on a visible side 21 or a visible surface of the cover element 20. The cover element 20 completely separates the switching arrangement 10 and the sensor element 30 from one another and makes them independent of one another, so that, in addition to the indirect connection via the cover element 20, there is only an operative connection via an electric field. For this purpose, the sensor element 30 is designed to generate an electric field and to detect a change and an associated position of the change in the electric field.The switching arrangement 10 is designed to cause the change in the electric field when actuated by an operator, which can be detected accordingly by the sensor element 30.

[0033] For this purpose, the switching arrangement 10 has a coupling electrode 11 coupled to the electric field, in the present case two switching elements 40 and each switching element 40, ie here two sensor electrodes 12 assigned to a respective predetermined position 13, 14, which are electrically connected to the coupling electrode 11 via the respective switching element 40 by electrical conductors 15.

[0034] If the operating element 50 is deflected from the neutral center position according to Figure 1 by a force K applied by the operator along the first actuation path X or in a first actuation direction into a first actuated position according to Figure 2, a first switching element 40 is actuated by the operating element 50, so that at the assigned first position 13, a change in the electric field coupled in via the associated sensor electrode 12, the electrical lines 15 and the coupling electrode 11 is generated at the first position 13, which change is detected by the sensor element 30. For the sake of clarity, it should be pointed out that the positions at which the sensor electrodes 12 are provided on the cover element 20 or on the base plate 16 do not have to be fixed.Accordingly, the sensor electrodes 12 can be positioned flexibly on the base plate 16 and / or the cover element 20, for example depending on a particular application.

[0035] In the event of a deflection in the direction opposite to the actuation path X by a correspondingly opposite force, a second, opposite switching element 40 is actuated by the operating element 50, so that at the associated second position 14, a change in the electric field is generated by the electric field coupled in via the associated sensor electrode 12, the electrical lines 15 and the coupling electrode 11, which change is detected by the sensor element 30.

[0036] For this purpose, the switching arrangement 10 has a base plate 16, which is fixed to the visible surface of the cover element 20 by an adhesive layer. The sensor electrodes 12 are arranged on the base plate 16 or between the base plate 16 and the visible side 21 of the cover element 20. A frame 17, which functions as a coupling electrode 11, is provided surrounding the base plate 16 and is fixed to the base plate 16 and / or also to the visible surface of the cover element 20.

[0037] A central support 18 extends orthogonally from the base plate 16 to the visible surface of the cover element 16, on which the two switching elements 40 are held on two opposite sides. Furthermore, the operating element 50, whose outer surface 51 directly serves as a gripping surface for the operator, is spring-returned to a neutral central position by spring elements 19.

[0038] The switching elements 40 have a movable electrically conductive contact body 41 for the switchable connection of the coupling electrode 11 to the sensor electrode 12, which is encased in an electrically non-conductive housing 42, so that projections 52 provided on an inner side of the operating element 50 can act on the housing 42 to establish the electrical connection.

[0039] With regard to the spring return of the operating element 50 to the neutral center position, it can alternatively be provided that the two switching elements 40 are spring-returned to an open, i.e., non-actuated, basic position, wherein the operating element 50, for example, in its neutral center position, rests directly against the switching elements 40 via the projections 52. If one of the switching elements 40 is spring-returned from an actuated position to its non-actuated basic position, the operating element 50 is spring-returned accordingly at the same time.

Claims

Patent claims 1. A capacitive operating unit (1) for a motor vehicle, comprising a capacitive sensor element (30) configured to generate an electric field and detect a change in the generated electric field, a switching arrangement (10) configured to effect a change in the electric field upon actuation by an operator, and a cover element (20) for contact-free separation of the sensor element (30) from the switching arrangement (10), on the closed visible side (21) of which the switching arrangement (10) is arranged, and on the opposite closed rear side (23) of which the capacitive sensor element (30) is arranged, wherein the switching arrangement (10) has a coupling electrode (11) coupled to the electric field, at least one switching element (40), and for each switching element (40) a sensor electrode (12) assigned to a predetermined position (13, 14).which are electrically connected to the coupling electrode (11) via the respective switching element (40) by electrical conductors (15), so that a change in the electric field detectable by the sensor element (30) can be effected by the at least one sensor electrode (12) upon actuation of the respective switching element (40) at the respective predetermined position (13, 14), wherein the switching arrangement (10) has an electrically non-conductive operating element (50) which can be actuated by the operator and which is designed to act directly in a switching manner on at least one of the switching elements (40) upon actuation.

2. Capacitive operating unit according to claim 1, wherein the switching arrangement (10) comprises a switch arranged on the visible side (21) of the Cover element fixed base plate (16) on which the sensor electrodes (12) are arranged.

3. Capacitive operating unit according to claim 2, wherein the coupling electrode (11) is designed as an electrically conductive frame (17) surrounding the base plate (16) and the sensor electrodes (12) on the cover element (20) or wherein the coupling electrode (11) is arranged on a frame (17) surrounding the base plate (16) and the sensor electrodes (12) on the cover element (20).

4. Capacitive operating unit according to one of the preceding claims, wherein the operating element (50) is designed to actuate the at least one switching element (40) in a translational movement relative to a visible surface of the cover element (20).

5. Capacitive operating unit according to one of the preceding claims, wherein the at least one switching element (40) has an electrically conductive contact body (41) for establishing the electrical connection between the coupling electrode (11) and the respective sensor electrode (12) and / or a housing (42) which can be acted upon to actuate the switching element (40).

6. Capacitive operating unit according to one of the preceding claims, wherein the switching arrangement (10) has a central support (18) extending orthogonally to the cover element (20), on which the at least one switching element (40) is held so as to be operable along a switching path (X) running parallel to the visible side (21) of the cover element (20).

7. Capacitive control unit according to one of the preceding claims, wherein the switching arrangement (10) has at least two switching elements (40) which are arranged opposite one another in pairs and can be actuated in opposite directions.

8. Capacitive operating unit according to one of the preceding claims, wherein the operating element (50) is formed in one piece and / or is spring-returned to a neutral central position and / or forms a gripping surface for interaction with the operator on an outer side (51) facing away from the at least one switching element (40).

9. Capacitive operating unit according to one of the preceding claims, wherein the cover element (20) directly forms a visible surface on its visible side (21) or wherein the cover element (20) has a decorative layer on its visible side (21) that substantially completely covers the visible side (21).

10. Capacitive operating unit according to one of the preceding claims, wherein the sensor element (30) is a capacitive touch foil extending flatly on the rear side (23) of the cover element (20). * * * * *

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