Components for capacitive sensor mechanisms

Abstract

The invention relates to a component (10) of a capacitive sensor mechanism (20) for a vehicle (1), in particular for driving and / or evaluating in a capacitive sensor mechanism (20) to detect activation behavior at the vehicle (1), comprising: at least one sensor electrode (20.1) for detecting changes in the environment of the vehicle (1); a transmission mechanism (30) for providing an output signal (A) by means of a frequency-dependent change of an electrical input signal (E) of the transmission mechanism (30); an output end (30.2) of the transmission mechanism (30), which is electrically connected to the sensor electrode (20.1) in order to drive the sensor electrode (20.1) with the output signal (A); wherein the transmission mechanism (30) has at least one filter element (30.4, 30.5) for performing the frequency-dependent change.

Description

Technical Field

[0001] The invention relates to an assembly of a capacitive sensor arrangement for a vehicle. The invention also relates to an exterior door handle and a method for operating a capacitive sensor arrangement for a vehicle. Background Art

[0002] It is known from the prior art to use capacitive sensor systems with sensor elements in vehicles in order to detect changes in the environment of the sensor element, such as movement or approach of a person. In order to evaluate the sensor element, it can be repeatedly charged and discharged, which is correspondingly accompanied by the transmission and reception of electrical signals in the sensor system. For this purpose, rectangular signals that may occur due to recharging and / or due to switching between discharge current path and charge current path are usually used.

[0003] For evaluating the sensor element, recharging methods are known, for example, as disclosed in DE 10 2012 102 422 A1, DE 10 2012 105 266 A1, DE 10 2013 112 909 A1 or DE 10 2013 112 910 A1.

[0004] A common problem here is that such evaluation signals and in particular rectangular signals can have a spectrum that contains unfavorable frequencies. It is therefore conceivable that interference radiation occurs at the sensor element during recharging with the aid of the signal. Accordingly, reducing the interfering effects of the sensor mechanism on the environment is usually a technical challenge and involves expensive measures. For example, problems may arise due to the interaction with radio signals in the range of 510 kHz to 1.71 MHz. Such radio signals are emitted, in particular, by external transmitters of medium-wave radio broadcasts (AM band) or the like. Here, measures for reducing and / or compensating for the interaction are usually technically complex and costly. Summary of the invention

[0005] The object of the present invention is therefore to at least partially eliminate the aforementioned disadvantages. In particular, the object of the present invention is to allow an improved operation of a capacitive sensor arrangement of a vehicle.

[0006] The aforementioned object is achieved by an assembly having the features of an independent device claim, an exterior door handle having the features of a further parallel device claim, and a method having the features of an independent method claim. Further features and details of the invention are derived from the respective dependent claims, the description and the drawings. Features and details described in relation to the assembly according to the invention are of course also applicable in relation to the exterior door handle according to the invention and the method according to the invention, and vice versa, so that reference is always made to one another or can be made to one another with regard to the disclosure of the respective inventive aspects.

[0007] This task is accomplished in particular by a component, in particular a circuit component, for a capacitive sensor system of a vehicle, which is preferably used for driving and / or evaluating in a capacitive sensor system to detect activation behaviors at the vehicle, for example at the front and / or side and / or rear of the vehicle. The activation behavior can be performed, for example, by a person in the vehicle environment. Thus, a person may wish to open the vehicle trunk lid by a gesture at the rear. The gesture is, for example, a movement of a body part under the bumper, which can be detected by the sensor system. It may also be possible to specify a gesture in the environment of a vehicle door handle as an activation behavior, for example in order to unlock and / or open a door.

[0008] Advantageously, the assembly of the invention has at least one of the following components:

[0009] at least one or exactly one sensor element in the form of a sensor electrode for detecting changes in the vehicle environment, in particular in the environment of the sensor element, preferably in the area outside the vehicle and / or in the area under the bumper and / or in the area of ​​the door handle, preferably for detecting gestures and / or activation actions,

[0010] a transmission device for providing an output signal by a frequency-dependent and / or phase-dependent change of an electrical input signal of the transmission device, wherein the input signal is preferably provided at an input of the transmission device,

[0011] - an output of the transmission means, which is (in particular electrically) connected to the at least one sensor electrode in order to drive the sensor electrode with the output signal, preferably by transmitting the output signal to the sensor electrode.

[0012] In this case, it is provided in particular that the transmission device has at least one filter element for carrying out the frequency-dependent change.

[0013] This has the advantage that the frequency spectrum of the input signal can be adjusted by the transmission mechanism, i.e., for example, (unwanted) interference frequencies of the input signal can be filtered out and / or interference frequency radiation can be avoided when driven with the output signal, in particular when the sensor electrode outputs the output signal. In this regard, the solution of the present invention is based in particular on the assumption that, with respect to possible interference frequencies, it is particularly problematic to use a rectangular signal as an output signal for the sensor electrode. It is possible that, without other measures, it may not be sufficient to ensure that the transmission of the output signal and / or the output at the sensor electrode does not have a disturbing influence on the output signal and / or the electromagnetic radiation at the sensor electrode. This can be avoided in that the at least one filter element is used to shape the output signal according to the input signal. The input signal specifies, for example, in the form of a rectangular signal, an evaluation sequence, i.e., a beat and / or a timing for the switching process of at least one switching element. The at least one filter element then causes shaping, i.e., an adjustment of the frequency components in the input signal, such as harmonic suppression. The transmission mechanism is adapted, for example, by correspondingly adjusting the filter element, for outputting a sinusoidal signal as an output signal. This has particularly advantageous properties with respect to the frequency spectrum.

[0014] Advantageously, only a single (structurally provided) sensor electrode can be provided in the assembly according to the invention for forming the (variable) sensor capacitance, wherein the counter-electrode for forming the sensor capacitance is preferably formed by the vehicle ground and is therefore not considered as a separate (dedicated) component. Preferably, the parasitic capacitance of the sensor arrangement is negligible in this case. This allows a very simple structural design.

[0015] The sensor element and in particular the sensor electrode can be a sensor element made of an electrically conductive material, for example, designed as an elongated (slim) electrical conductor, for example in the form of a cable, and optionally connected to the vehicle electronics only via a single direct electrical connection.

[0016] In this context, electrical connection can be understood not only as a direct connection but also as an indirect connection, i.e. also via other electrical components, but preferably only when the connection is made exclusively electrically. For example, an electric field between a sensor electrode and vehicle ground cannot be understood in this case as a direct electrical connection, so that the sensor electrode preferably has only a single direct electrical connection to the vehicle electronics. The vehicle electronics may also be understood as at least the sensor device and / or the control device and / or the transmission device.

[0017] The vehicle is preferably designed as a car, preferably a sedan and / or an electric car and / or a hybrid car and / or an autonomous vehicle.

[0018] It is also conceivable that the at least one sensor element, preferably the at least one sensor electrode, is arranged at the front and / or side and / or rear of the vehicle in order to detect changes in the environment and / or corresponding activation behaviors in the environmental area, i.e. the front and / or side and / or rear of the vehicle. In this way, activation behaviors in the environmental area can be reliably detected by the sensor mechanism. For example, components and / or functions of the vehicle can be moved or activated in the environmental area intuitively based on the detection. Such functions are, for example, the lighting of the vehicle and / or the unlocking of the vehicle locks and / or the like. The components can be designed, for example, as a trunk lid and / or a side door and / or a sliding door and / or a hood, which are moved and / or opened and / or closed based on the detection. It is also possible that the sensor element is arranged at and / or in the threshold or in the threshold area in order to, for example, open the side door or sliding door of the vehicle based on the detection. In order to reliably detect the movement and / or the form of movement based on the detection, at least two sensor elements, preferably sensor electrodes, can also be provided as an alternative or supplement to the aforementioned features. For example, they are arranged together in at least one of the aforementioned surrounding areas, for example, together in a bumper or a door sill or a door handle or the like.

[0019] Preferably, the capacitive sensor mechanism can have the sensor element (or sensor electrode) and / or the transmission mechanism and / or the controller. The drive in the capacitive sensor mechanism can mean that the transmission mechanism outputs the output signal, which is transmitted to the sensor element for charging. The evaluation can mean that a holding mechanism of the controller receives the charge of the sensor element by receiving the signal, which can be evaluated, for example, to detect an activation behavior. Therefore, a holding mechanism of the controller can advantageously be provided in order to evaluate the sensor element (i.e., in particular the sensor electrode), the holding mechanism being evaluated, perhaps by a driver, to allow reliable detection.

[0020] Furthermore, it can be provided in the assembly according to the invention that the at least one filter element influences not only the output of the output signal (at the output or the transmission path) but also the charge reception from the sensor electrode to the holding means by means of the reception signal (at the reception path), preferably by means of a frequency-dependent change. This can be achieved, for example, in that the holding means is electrically connected to the transmission means.

[0021] It can further be advantageously provided that the transmission means is formed by the at least one filter element in the form of an active electronic filter, preferably a Sallen-Key filter. This has the advantage that the output signal, in particular as a guided signal, contains the frequency behavior caused by the at least one filter element very reliably.

[0022] Preferably, it can be provided that the transmission mechanism forms an all-pass filter or a low-pass filter by means of the at least one filter element, so as to preferably filter the input signal in such a way that, when driving the sensor electrode, the radiation in the interference frequency range is at least reduced, preferably from the second harmonic of the input signal. In other words, it can be provided that the transmission mechanism is designed to perform harmonic suppression of the input signal, so as to perform harmonic suppression when the sensor electrode outputs the output signal. This has the following advantages, namely, the transmission mechanism can form a harmonic filter to at least reduce the interference caused by the output signal. The interfering frequency range is in particular a predetermined frequency range here, and depends, for example, on the transmitter and radio frequency used in the area, etc. Harmonics preferably represent vibrations with a frequency corresponding to an integer multiple of the fundamental frequency of the input signal. The fundamental frequency is, for example, a basic operating frequency of 333 kHz. Harmonics higher than the fundamental frequency are also referred to as resonances or higher harmonics here.

[0023] It can be particularly advantageously provided in the assembly of the invention that the at least one filter element is designed to form an electronic filter, preferably a low-pass filter and / or a band-pass filter, in order to preferably perform a frequency-dependent change of the input signal, wherein the at least one filter element is particularly preferably connected to a source mechanism as another filter element, thereby forming an active filter, particularly preferably a Sallen-Key filter. The source mechanism is, for example, a controlled source mechanism, in particular a voltage source mechanism. It can refer to a real electrical element or circuit, whose function is similar to an ideal controlled source (i.e. a "dependent source"), in particular an ideal controlled voltage source. Therefore, the source mechanism can be understood as a real controlled source, in particular a real voltage source (CVS). An example of such a source mechanism is an operational amplifier (OP), in particular a controlled, preferably voltage-controlled operational amplifier. It is particularly advantageous that the source mechanism is designed as a (real) low-impedance controllable (voltage) source. This has the advantage that the output signal as a guided output signal very reliably maintains the signal shaping.

[0024] According to another possible approach, it can be provided that the at least one filter element comprises a first filter element, in particular for forming an RC low-pass filter, and a second filter element, in particular for forming a Sallen-Key filter, wherein these filter elements are connected to one another in order to jointly perform a frequency-dependent change of the input signal. Preferably, the second filter element can also have an operational amplifier. It can particularly reliably filter out interfering frequencies, since a sinusoidal signal can be provided.

[0025] Advantageously, it can be provided within the scope of the invention that the output signal can be provided in such a way as to vary the input signal in accordance with the frequency, that is, the at least one filter element is connected between the output and the input of the transmission mechanism. In particular, the provision of the output signal is carried out in such a way that the input signal varied by the filter element is applied to the control input of the source mechanism in order to control the source mechanism with respect to the output of the output signal, and the output of the source mechanism is connected to the output of the transmission mechanism or corresponds thereto. In addition, feedback can also be provided in the source mechanism in order to use an operational amplifier as the source mechanism. The operational amplifier can possibly provide an amplification with an amplification factor of 1 between the (e.g. non-inverting) input and the output of the operational amplifier.

[0026] It may also be possible to connect an input signal source to the input of the transmission mechanism in order to preferably provide an input signal at the input in the form of a signal based on a rectangular signal, which is actively modified, in particular by signal shaping, preferably by smoothing the edges of the rectangular signal and / or by time-varying amplitudes, in particular for rectangular signal pulses within the pulse length, in order to preferably assist the frequency-dependent modification of the transmission mechanism, preferably harmonic suppression. It is advantageous here that the input signal source, preferably the driver and / or the drive assembly, provides a first signal shaping in advance. This can facilitate further shaping by the at least one further filter element. For this purpose, the rectangular signal (i.e. at least a rectangular signal, possibly with interruptions) is pre-filtered, for example, by the input signal source, so that a preliminary attenuation of harmonics is performed in advance, which is further amplified by the transmission mechanism.

[0027] Alternatively, it is conceivable that a driver is provided as part of the input signal source for generating the input signal, preferably by means of a digital-analog converter. The digital-analog converter is, for example, part of the driver and / or is designed separately therefrom. In the generation, signals other than rectangular signals can already be provided, which, for example, have smoothed edges. The generation of the input signal is set, for example, by means of a regulating mechanism.

[0028] It is also conceivable that, for signal shaping of the input signal, a driving component is provided as part of the input signal source, which is preferably connected between the input end of the transmission mechanism and the driver, so as to preferably change the input signal generated by the driver through signal shaping and load it on the input end of the transmission mechanism. Therefore, the driving component can be used as a resistor network or the like for shaping and / or pre-filtering of the input signal in advance.

[0029] Preferably, the invention provides that, as part of the source of the input signal, the driver is designed to actuate the drive assembly in such a way that the input signal corresponds to a rectangular signal which switches back and forth between a first value and a second value, wherein the first value and the second value preferably change over time, first increasing and then decreasing. In other words, the pulses of the signal output successively in time can have different (maximum) amplitudes. This can result in step-shaped shapes in the input signal, which can particularly effectively promote the shaping of the signal through the at least one filter element and / or the frequency-dependent change.

[0030] Further advantages can be achieved within the scope of the invention in that a switching element is connected between the output of the transmission mechanism and the sensor electrode in order to controllably, preferably repeatedly and / or timedly connect the receiving path and the transmitting path alternately to the sensor electrode (preferably by means of a driver), wherein preferably the output is (particularly directly) connected to the transmitting path and / or the holding mechanism is (particularly directly) connected to the receiving path for evaluation at the sensor mechanism. This allows, for example, the implementation of a recharging method for evaluating a variable capacitance (sensor capacitance) provided by the sensor electrode. The switching element is designed, for example, as an electronic switch, which can be switched electrically by means of the driver.

[0031] It is also conceivable in the assembly according to the invention that the output of the transmission mechanism is connected to the sensor electrode via at least one switching element, wherein the switching element is preferably connected to a driver in order to repeatedly and preferably timedly output the output signal at the sensor electrode. For this purpose, the driver can, for example, be connected to a control input of the switching element for switching. Alternatively or additionally, it is conceivable that the holding mechanism is connected to the sensor electrode via the at least one switching element, wherein the switching element is connected to the driver in order to repeatedly and preferably timedly connect the holding mechanism to the sensor electrode, preferably alternating with the output signal output at the sensor electrode. This allows, in particular, the implementation of a recharging method.

[0032] Optionally, provision can be made for the evaluation in the sensor device to integrate a holding device in the receiving path in order to receive a receiving signal, preferably after charging the sensor electrode by the output signal, as a function of the charge stored in the sensor electrode and / or as a function of the variable sensor capacitance of the sensor device, wherein the sensor electrode is designed to provide the sensor capacitance. This makes it possible to detect activation behaviors in the environment in a simple manner when the sensor capacitance changes significantly.

[0033] It can also be provided within the scope of the invention that the sensor electrode is designed to be able to establish an operative electrical connection with the vehicle environment, preferably to be arranged in a bumper or door handle of the vehicle, so that when the sensor electrode is driven an electric field is generated in the environment for providing a variable sensor capacitance as a function of the environment. A sensor element designed as a sensor electrode is advantageous here, in particular also for such an arrangement in a door handle or bumper, since the sensor electrode can be designed to be flexible or bendable or elastic or to save space.

[0034] It may also be advantageous within the scope of the invention to provide a holding device for evaluating the variable sensor capacitance in order to detect changes in the vehicle environment preferably based on the evaluation, wherein the holding device is preferably designed as an integrator in order to carry out charge accumulation, in particular based on the charge stored in the sensor electrode. In other words, the holding device can temporarily store the amount of charge received by the sensor electrode by receiving the signal by means of the holding capacitor (perhaps also via a current mirror). In addition, the holding device can also have a circuit with at least one operational amplifier, which is designed with frequency-dependent negative feedback, preferably via at least one capacitor, to form an integrator. This allows a particularly simple and inexpensive evaluation.

[0035] It is also conceivable that the transmission mechanism is connected to the holding mechanism in order to receive the received signal from the sensor electrode at the holding mechanism according to the frequency-dependent change, preferably in order to also provide the frequency-dependent change for the received signal for evaluation at the sensor mechanism, i.e. in particular to receive the received signal from the sensor electrode according to the frequency-dependent change. For example, by using feedback for evaluating the received signal at the holding mechanism, the signal changed by the at least one filter element can influence the received signal here. The changed signal is conducted from the transmission mechanism to the holding mechanism, such as an integrator input, for example, via an electric line. Thus, an advantageous frequency adjustment by means of the transmission mechanism can be provided not only for output signals, i.e. for driving, but also for received signals, i.e. for evaluation.

[0036] It is further advantageous within the scope of the invention if an operational amplifier input of the transmission device (preferably an operational amplifier for providing an active filter) is connected to a (first) integrator input of the holding device in order to preferably receive a receive signal from the sensor electrode according to the frequency-dependent change, whereby the frequency-dependent change is preferably provided both in the receive path for the receive signal and in the transmit path for the output signal. The connection between the transmission device and the holding device is preferably also used to shape the receive signal in the evaluation, whereby the receive path is preferably connected to the second integrator input of the holding device. In this way, spectral influences, in particular harmonic suppression, can be brought about not only in the output signal but also in the receive signal by the frequency-dependent change. Interference can also be avoided to a greater extent thereby.

[0037] It is also conceivable that the transmission mechanism forms a filter with low-pass filter performance, whose limit frequency is in the range of 100 kHz to 800 kHz, preferably 200 kHz to 600 kHz, preferably 400 kHz to 550 kHz, and particularly preferably 470 kHz. This can be provided in particular by correspondingly adjusting the elements of the transmission mechanism. Alternatively or additionally, the transmission mechanism can be designed to have the filter performance of an active low-pass filter, in particular third-order and / or attenuation of up to -20 dB at 1 MHz and / or with a limit frequency of 470 kHz. In other words, a harmonic suppression of at least -20 dB can be provided. The filter is particularly suitable here for operating frequencies of the sensor mechanism 20 (essentially) up to 333 kHz, which can be determined by the switching frequency between the recharging phase and / or the transmission phase. In particular, harmonics can be effectively suppressed from the second harmonic or the third harmonic.

[0038] The subject matter of the invention is also an outer door handle for a vehicle, which has an assembly according to the invention, wherein the outer door handle is designed, for example, for attachment to a side door or a trunk lid of the vehicle.

[0039] Protection is also claimed for a sensor arrangement having a component according to the invention.

[0040] A method for operating a capacitive sensor arrangement of a vehicle is also claimed, in particular for driving and / or evaluating in a capacitive sensor arrangement to detect an activation behavior at the vehicle, preferably at the side and / or front and / or rear of the vehicle. Provision is made here for the sensor arrangement to have at least one sensor electrode for providing a sensor capacitance.

[0041] Advantageously, at least one of the following steps can be performed in the method according to the invention, wherein the steps can preferably be performed successively in the order described or in any order, and individual steps can optionally also be repeated:

[0042] a) switching at least one switching element to connect the transmission path to the sensor electrode,

[0043] b) generating an electrical input signal, in particular at the input of a transmission mechanism, preferably via a driver such as a microcontroller,

[0044] c) performing a frequency-dependent transformation of the electrical input signal in order to provide an output signal, preferably at the output of the transmission device, preferably via the transmission device, particularly preferably via at least one filter element,

[0045] d) outputting the output signal at the sensor electrode via a transmission path,

[0046] e) switching the at least one switching element to connect the receive path to the sensor electrode and preferably to remove the connection to the transmit path,

[0047] f) Transmitting a received signal from the sensor electrode to a holding device in a receive path in order to evaluate the sensor capacitance.

[0048] For this purpose, the method according to the invention brings the same advantages as those explicitly described with respect to the assembly according to the invention.In addition, the assembly according to the invention can be driven according to the method according to the invention.

[0049] According to an advantageous development of the invention, it can be provided that harmonic suppression is achieved not only in the output signal but also in the received signal by means of a frequency-dependent change. This can preferably be achieved by means of a connection between the holding device and the transmission device. This allows interference to be continuously avoided when the sensor element is driven.

[0050] Preferably, it can be provided within the scope of the invention that the generation of the electrical input signal is repeatedly interrupted in the form of a periodic signal to provide an interruption phase in order to suspend the output of the output signal and in particular also the transmission of the received signal, preferably in such a way that the output signal is output in the form of a pulse train signal. In other words, the pause can be performed after repeated transmission of the output signal to the sensor electrode and the transmission of the received signal from the sensor electrode. The pause, i.e. the interruption phase, can be performed regularly in this case to reduce energy consumption. To achieve this, for example, a "zero signal", i.e. a voltage of 0 volt, etc., is output as an input signal by the driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Further advantages, features and details of the invention are derived from the following description of embodiments of the invention with reference to the accompanying drawings. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination, wherein:

[0052] Figure 1 A perspective view of the rear of the vehicle with the user is shown,

[0053] Figure 2 A schematic circuit diagram showing the sensor mechanism,

[0054] Figure 3 A schematic diagram showing the components of the present invention,

[0055] Figure 4 A schematic diagram showing the sensor mechanism,

[0056] Figure 5 A schematic diagram showing the signal change curve,

[0057] Figure 6 Another schematic diagram showing the assembly of the present invention. DETAILED DESCRIPTION

[0058] In the following figures, the same reference numerals are used for the same technical features even in different embodiments.

[0059] Figure 1 A perspective view of a vehicle 1 is schematically shown. A trunk lid 2 is shown above a bumper 3 of the vehicle 1, where the trunk lid 2 can be opened, for example, according to a (first) vehicle function and / or can be closed again according to a (second) vehicle function. At least one sensor element 20.1, in particular a sensor electrode 20.1, of a capacitive sensor mechanism 20 can be incorporated into the bumper 3. Alternatively or additionally, at least one sensor element 20.1 can also be integrated into an (external) door handle 4 or other vehicle component of the vehicle 1. The capacitive sensor mechanism 20 accordingly has a capacitive sensor, which is at least partially formed by the sensor element 20.1. The sensor element 20.1 is preferably designed to be cable-shaped and / or to have an elongated extension shape to provide as wide a detection range as possible to detect activation behavior. It is also conceivable that the sensor element 20.1 has an extension shape different from the elongated extension shape, for example, a substantially circular or rectangular or dot-shaped shape, etc. The activation behavior is, for example, a movement of an activation medium 9, such as a body part 9, especially a foot 9, of a user 8 in an environment outside the vehicle 1 or the sensor element 20.1. To perform the activation behavior, the user 8 can move the activation medium 9 under the bumper 3. This movement is then detected as a change in the sensor capacitance CS of the capacitive sensor device 20 and can preferably be evaluated and detected by the controller 50 of the sensor device 20. For this purpose, the controller 50 is electrically connected and / or wired to the sensor element 20.1. Accordingly, it may be meaningful that the controller 50 is designed as a control device of the vehicle 1, preferably a part of the vehicle electronics or electrically connected to it. At this time, it is conceivable that, in order to reduce the circuit costs, only a single electrical connection, such as a single wire such as a cable, is laid from the controller 50 to the sensor element 20.1, that is, it is connected only by a single conductive connection. As a result, the sensor element 20 is a sensor electrode 20.1 for providing the sensor capacitance CS. It is also possible that the detection of the activation behavior is performed by the controller 50, and the controller 50 then activates the vehicle function or at least one of the vehicle functions.

[0060] exist Figure 2 The detection principle for detecting activation behavior and evaluating the sensor capacitance CS is shown in detail in the circuit diagram of the capacitive sensor device 20 and the assembly 10 according to the invention, in particular the circuit assembly 10. Only one sensor element 20.1 or possibly also a plurality of sensor elements 20.1 can be provided. For example, Figure 22 shows two sensor elements 20.1 in the form of sensor electrodes 20.1, which can each provide a sensor capacitance CS. In other words, the corresponding sensor element 20.1 or sensor electrode 20.1 can provide a corresponding capacitive sensor, which can each be understood as a capacitor. In the case of a plurality of sensor elements 20.1, at least one switching mechanism 60 with at least one selective switch can be provided, by which the sensor elements 20.1 are selected in turn, i.e. an electrical connection is established therewith. The at least one switching mechanism 60 here connects the sensor elements 20.1, for example, in turn to the pre-filter component 80 and / or to the at least one switching element S. The use of at least two sensor elements 20.1 has the advantage that, for example, a movement and / or a form of movement can be detected.

[0061] The respective sensor element 20.1 can have an electrically conductive material for forming a (single) sensor electrode 20.1 in each case. In this case, it is sufficient to provide the sensor capacitance CS by merely providing the respective sensor electrode 20.1 without a counter electrode. In this case, Figure 2 The counter-electrodes shown (relative to the respective sensor elements 20.1) are only schematic for explaining the principle and should not be regarded as actual components. Alternatively, at least one counter-electrode may be provided on the structure or a corresponding counter-electrode may be provided for each sensor element 20.1.

[0062] Each sensor element 20.1 can form a sensor capacitance CS relative to a ground potential 20.2, in particular the vehicle ground, and relative to the environment of the vehicle 1. The sensor capacitance CS can therefore change due to the environment of the vehicle 1, that is, in particular when the activation medium 9 moves into the surrounding area of ​​the sensor element 20.1. In this way, the activation behavior can be detected very reliably based on the sensor capacitance CS.

[0063] Various different methods are considered for evaluating the sensor capacitance CS. The methods are based in particular on the fact that the charge located in the sensor element 20.1 or stored by means of the sensor capacitance CS can be transferred to a holding device 50.4 having a holding capacitance CH. In this case, use is made of the fact that the stored charge is dependent on the variable sensor capacitance CS and thus on the environment of the vehicle 1 (such as activation behavior). The holding device 50.4 can in this case have a holding capacitor, which is used for charge storage and / or charge temporary storage and for charge evaluation by means of the controller 50. Advantageously, the holding device 50.4 has an operational amplifier OP', which may form an integrator with at least one further element and / or a feedback element (perhaps designed as a phase-dependent and / or frequency-dependent) (such as via a capacitor) (see also for this purpose Figure 6). The integrator is used to store a charge quantity which is specific to the charge quantity received by the sensor element 20.1 during recharging via the received signal. The operational amplifier OP' can be connected via the output O, perhaps via an analog-digital converter 50.2, to a driver 50.1, for example in the form of a microcontroller, in order to evaluate the stored charge quantity.

[0064] For recharging, a repeatedly executed receiving phase (also called recharging phase) can preferably be used. The receiving phase can be a certain switching phase, i.e. a switching state of at least one switching element S. For this purpose, for example, the at least one switching element S, in particular the at least one changeover switch S, is repeatedly switched, preferably at a frequency of 333 kHz. In this case, the receiving phase is entered when the switching element S electrically connects the receiving path r to the sensor element 20.1. After the switching element S is further switched to another switching state, a transmission phase (perhaps also called charging phase) is entered, in which the switching element S electrically connects the transmitting path t to the sensor element 20.1. The two paths r and t can be designed here as conductors (for example on a printed circuit board), which thus provide an electrically conductive connection.

[0065] The transmission phase can be used to supply the sensor element 20.1 with charge, i.e., to cause the capacitive sensor to be charged. For this purpose, the sensor element 20.1 is electrically connected to the transmission mechanism 30, for example, via the switching element S and via the transmission path t in the transmission phase. This causes the output signal A to be transmitted to the sensor element 20.1 via the transmission path t, in particular from the transmission mechanism 30. The receiving phase can be used to receive the charge located therein (because the sensor capacitance CS is stored), i.e., to cause recharging. For this purpose, the sensor element 20.1 is electrically connected to the holding mechanism 50.4, for example, via the switching element S and via the receiving path r in the receiving phase. This causes the received signal to be transmitted to the holding mechanism 50.4, in particular from the sensor element 20.1, via the receiving path r. In addition, the switching mechanism 60 can also be repeatedly switched to connect different sensor elements 20.1 to the receiving path and the transmitting path r, t in turn.

[0066] Below, the receiving phase is discussed in detail, which can be used for evaluation in the sensor device 20. In the receiving phase, the charge stored by means of the sensor capacitance CS can be "transferred", that is, the holding device 50.4 (such as a holding capacitor) with the holding capacitance CH is charged according to the sensor capacitance CS or the charge stored thereby (such as proportionally thereto). Here, the recharging may be carried out by a low-pass filter 50.5 and / or, for example, also by a current mirror that is not explicitly shown. The charge state of the holding device 50.4 or the holding capacitor, which is subsequently relevant to the detection of the activation behavior, can be determined, in particular, by the voltage through the capacitor or connected in series to the holding capacitor, optionally by an analog-digital converter 50.2. For this purpose, the analog-digital converter 50.2 can be connected to the holding device 50.4, for example, via a low-pass filter 50.5, and to the driver 50.1 on the other hand. In addition, at least one other control element 50.7 (also called compensator) can also be optionally connected to the receiving path r, so as to, for example, perform compensation for the excess charge during recharging. For this purpose, the control element 50.7 can, for example, include a regulating circuit. Therefore, the control 50.7 (perhaps together with other components such as the driver 50.1) can be designed to detect a charge surplus (ie when the amount of transferred charge can no longer be stored by the holding capacitor CH) and / or to perform compensation.

[0067] The driver 50.1 of the controller 50 can be designed, for example, as a microcontroller or the like and can also (especially repeatedly and / or timedly) switch the switching element S. In particular, the driver 50.1 can perform this switching in accordance with at least one regulating mechanism 50.3, preferably a computer program, in order to thereby determine and / or change the phase duration of the reception phase and / or the transmission phase. In addition, the alternating execution of the reception phase and / or the transmission phase can also be interrupted by the driver 50.1, i.e. a further interruption phase can be introduced. This serves, for example, to suspend the output of the output signal A and / or to suspend the transmission of the reception signal, in order, for example, to reduce energy consumption.

[0068] according to Figure 2 The circuit diagram of FIG. 1 clearly shows that a rectangular signal for driving and / or evaluating sensor element 20 . 1 is generated, in particular by switching of the switching element S described, without further measures. It accordingly has a very broad spectrum. Without further measures, this unfavorable spectrum could result in sensor element 20 . 1 causing interfering electromagnetic radiation (emissions) in the environment of vehicle 1 , in particular in frequency ranges that could have an interfering effect on other radio signals, etc.

[0069] Therefore, it can be provided as a measure within the scope of the invention that a phase-dependent and / or frequency-dependent transmission and / or change of at least one signal is performed for driving and / or evaluation. Thus, for example, a signal, namely an output signal A, can be output and / or generated directly at the output 30.2 of the transmission device 30 for driving (i.e. for transmission to the sensor element 20.1 and / or for charging and / or driving the sensor element 20.1), where the signal spectrum width, in particular harmonics and thus interference effects can be reduced by signal shaping and / or filtering. As a further signal, the received signal of the sensor element 20.1 can also be influenced for evaluation by the phase-dependent and / or frequency-dependent transmission or change, for example by connecting the transmission device 30 to the holding device 50.4 in order to thereby control the reception of the received signal.

[0070] It is also advantageous if the signal and / or the signal shaping is influenced by a driver 50.1 and / or a driver component 50.6 connected to the driver 50.1 and / or integrated therein. These can be connected to the input 30.1 of the transmission mechanism 30 in order to provide the transmission mechanism 30 with an input signal E (in particular a drive signal E) at the input 30.1. In this way, the transmission mechanism 30 can be connected between the driver 50.1 and the sensor element 20.1 in order to perform a frequency-dependent and / or phase-dependent transmission or change for the input signal E. This is particularly advantageously carried out as a frequency filter in such a way that interfering frequencies in the input signal E are largely filtered out. For this purpose, the input signal E can be filtered when applied to the input 30.1 of the transmission mechanism 30 and output as an output signal A at the output 30.2. It is also possible to output the guided output signal A via the transmission mechanism 30 in accordance with the transmitted / changed (in particular filtered) input signal E. This ensures that the shape of the transmitted or modified or filtered signal and thus the filtered spectrum is also preserved at the sensor element 20.1. "Directed" can mean, in particular, that the output signal A is actively generated as a function of the transmitted or modified or filtered input signal E and is applied to the sensor element 20.1, for example by using an operational amplifier OP.

[0071] As from Figure 2 And more specifically, Figure 6As can be seen schematically in the figure, the transmission mechanism 30 can also be connected to the input of the holding mechanism 50.4. Here, the holding mechanism 50.4 comprises, for example, an integrator. For example, it can be provided that the input of the transmission mechanism 30, in particular the non-inverting input "+" of the operational amplifier OP of the transmission mechanism 30, is connected to the input of the integrator, preferably the (non-inverting) input "+" of another operational amplifier OP' of the integrator. Preferably, the connection is designed to allow the holding mechanism 50.4 to receive the received signal from the sensor element 20.1 via the receiving path r in accordance with the transmission and / or change in frequency and / or in phase caused by the transmission mechanism 30. To this end, the signal provided by the transmission mechanism 30 and having a change in frequency and / or in phase due to filtering (for example in Figure 3 and Figure 6 The "+" input of the operational amplifier OP in the integrator) for example affects the function of the holding mechanism 50.4 or the integrator. When connected to the integrator input, the provided signal can be understood as a kind of integration reference (for example, due to the connection to the non-inverting operational amplifier input of the integrator, the provided signal affects the differential voltage of another operational amplifier OP' of the integrator, and perhaps also affects the received signal through feedback in the operational amplifier OP'). Figure 6 The connection of the elements shown here corresponds to Figure 2 and Figure 3 , as shown by the connecting dashed lines.

[0072] exist Figure 3 30. The transmission mechanism 30 is shown in more detail in FIG. The circuit for generating the input signal E, i.e., in particular the controller 50, preferably the driver 50.1 and / or the driver component 50.6, is schematically represented by the input signal source 40. It is capable of generating an electrical input signal E, such as at least one input signal E in the form of a substantially rectangular signal or based thereon. The driver component 50.6 may also perform further signal shaping of the input signal E, for example, by means of a switchable resistor, in order to shape the input signal E. For this purpose, the driver component 50.6 may also be controlled by the driver 50.1, so as to perform signal shaping, for example, under the control of the adjustment mechanism 50.3. The input end 30.1 is electrically connected to at least one first filter element 30.4 (in particular an RC circuit) and / or a second filter element 30.5 (in particular a further resistor R and / or a capacitor C) to form a Sallen-Key filter. The first filter element 30.4 comprises, for example, a (perhaps only) resistor R and a (perhaps only) capacitor C. Preferably, a third-order filter can be provided by the transmission mechanism 30 as a whole by connecting these two filter elements 30.4, 30.5. The use of an operational amplifier OP also allows the construction of an active filter, preferably a Sallen-Key filter.

[0073] exist Figure 2In the diagram, the driver 50.1 is schematically connected to the driver component 50.6 via a wire. A circuit diagram can be simply shown here, where the wire can perhaps also be understood as a plurality of wires, which connect the respective output of the driver 50.1 to the respective resistor of the driver component 50.6. Thus, the driver 50.1 can be connected to the driver component 50.6, for example, via at least one or two or three or four separate wires, in particular in order to control at least one resistor of the driver component 50.6 respectively via the wires. In addition, the wires can, for example, respectively connect the respective outputs of the driver 50.1 to at least one resistor of the driver component 50.6, and preferably then electrically connect the respective outputs to the input 30.1 via the respective resistor(s). For example, the driver component 50.6 comprises at least two or three or four resistors, which are respectively connected to the driver 50.1 via respective wires with a first terminal and to the input 30.1 with a second terminal. In this case, it is the different wires and outputs of the driver 50.1 that the resistors can be driven individually and / or independently of each other in order to provide a shaped input signal E at the input 30.1. In other words, a programmable voltage divider is formed by the driver component 50.6. It allows shaping of the input signal E, such as Figure 5 As detailed.

[0074] It can be seen that the filter elements 30.4, 30.5 can be electrically connected to a source mechanism 30.3, in particular a current source mechanism and / or a voltage source mechanism 30.3. Figure 3In the example shown, the source mechanism 30.3 is designed as an operational amplifier OP, which is connected to the filter elements 30.4 and 30.5 in the sense of the Sallen-Key filter configuration. Accordingly, the operational amplifier OP and / or the source mechanism 30.3 may also refer to another filter element. According to the input signal E filtered by the filter elements 30.4 and 30.5, the source mechanism 30.3 causes the output signal A to be output at the output end 30.2. In order to actively transmit the output signal A, the source mechanism 30.3 is connected to the supply voltage. Here, for example, a first voltage U1 for providing a first supply potential VE and a second voltage U2 for providing a second supply potential VC are shown, wherein the voltages are, for example, equal in value but of different polarities. U1 is, for example, -5V, and U2 is, for example, +5V. By designing the components accordingly, the following transmission mechanism 30 can be provided, which has the filter performance of an active low-pass filter, in particular a third-order and / or an attenuation of -20dB at 1 MHz and / or a limit frequency of 470 kHz. In other words, a harmonic suppression of at least -20 dB can be provided. The filter is particularly suitable for operating frequencies of the sensor device 20 (substantially) up to 333 kHz, which are determined by the switching frequency between the receiving phase and / or the transmitting phase. For example, the operating frequency (or also other operating frequencies) is thus determined by the switching frequency of the switching element S or corresponds thereto. In particular, harmonics starting from the second harmonic or the third harmonic can be effectively suppressed.

[0075] Alternatively, it is also possible to dispense with the filter elements 30.4, 30.5, so that the transmission mechanism 30 has, for example, only a controlled source mechanism 30, so that the input signal E is transmitted substantially unchanged and then outputted unfiltered (e.g. in the form of a rectangular signal) as an output signal A. In addition, the transmission mechanism 30 can also have filter properties such as all-pass filtering.

[0076] Another alternative and / or supplementary embodiment of the assembly 10 of the present invention is Figure 330.3', to provide an alternative output terminal 30.2'. This design is only optional here, so as to utilize, for example, a current source and / or a converter as another source mechanism 30.3', so as to output the guided output signal A' in an alternative manner. In addition to the shown design with the operational amplifier OP, a design with another source mechanism 30.3' can be adopted, or it can also be used to replace the source mechanism 30.3. In the latter case, the filter composed of the filter elements 30.4 and 30.5 can also be designed as a passive filter, and / or the other source mechanism 30.3' is also designed as a filter element to form an active filter. In principle, the output signal A or A' can therefore be a forcedly transmitted sensor voltage or a forcedly transmitted sensor current.

[0077] exist Figure 4 , the transmission route of the signal S' between the switch element S and the at least one sensor element 20.1 is shown. Other electronic components can also be arranged along the transmission path u within the transmission route, which is indicated by the dotted line of the transmission path u. Other components can, for example, cause further filtering of the signal S'. The switch element S connects the transmission path to the receiving path r for evaluation or to the transmitting path t for driving, depending on the switch position (switching state). In the first switch position of the switch element S, the signal S' can therefore correspond to the output signal A, which is transmitted from the output end 30.2 of the transmission mechanism 30 to the sensor element 20.1. In the second switch position of the switch element S, the signal S' can correspond to the received signal and be transmitted to the holding mechanism 50.4 via the receiving path r. In the latter case, the signal S is dedicated to the detection and can, for example, be evaluated by the controller 50 to detect the activation behavior.

[0078] Also like Figure 4As shown, a prefilter component 80, in particular a preselector 80, can be used, preferably in the form of a notch circuit and / or a bandpass filter or a bandstop filter (bandstop filter device). In this way, interfering frequencies of the signal S' that may occur due to the sensor element 20.1 (in the sense of incidence or intrusion) can be filtered out. It is clear from this that the sensor element 20.1 can also be designed as an antenna, via which radiation emission (from the sensor device 20 to the environment of the vehicle 1) and radiation intrusion (from the environment to the sensor device 20) can occur. The expressions "emission" and "intrusion" are used in this case in the sense of interfering radio signals or electromagnetic radiation. The prefilter component 80 can be designed, for example, as an LC oscillating circuit and / or a notch circuit, for example, including a capacitor C and a coil L connected in parallel with each other. The prefilter component 80 is connected, for example, to a first terminal and a second terminal 80.1, 80.2. Advantageously, the first terminal 80.1 can connect the prefilter component 80 to a supply potential, and / or the second terminal 80.2 can connect the prefilter component 80 to a ground potential. This has the following advantage, namely, the signal components of the signal S' in the undesirable frequency range can be conducted, i.e., led away, through at least one of the terminals. For this purpose, the pre-filter component 80 is low-impedance for the frequency range that may be undesirable. However, for the desired frequency, the pre-filter component 80 can be high-impedance, so that for this frequency, the signal S' is not conducted through the pre-filter component 80 (the pre-filter component 80 therefore acts as a bandpass filter for the desired frequency in the following manner, i.e., the pre-filter component 80 does not exclude the desired frequency). Therefore, in an ideal case, i.e., when driven only with the signal S' having the desired frequency, no loss caused by filtering occurs. The power loss can be significantly reduced accordingly through the structure. It is also possible to add resistors and / or resistor components for the pre-filter component 80 in the receiving path r and the transmitting path t, respectively, where the resistors and / or resistor components are preferably designed to be (substantially) the same (having the same resistance value and / or the same size and / or the same impedance). The resistors and / or resistor components can be designed to adjust the transmission function of the pre-filter component 80.

[0079] Figure 5Different possibilities II to V for signal shaping of an input signal E (solid line) and the resulting output signal A (dashed line) are shown. For illustration, diagram I is shown, where no frequency- and / or phase-dependent change of the input signal E takes place by the transmission mechanism 30 and / or only a frequency- and / or phase-dependent transmission of the input signal E takes place. In diagram II, however, the filtering of the input signal E is performed by the transmission mechanism 30, i.e., in particular by means of a filter element. In this case, the filter element preferably provides an analog low-pass filtering, which changes the rectangular shape of the input signal E. In this way, a sinusoidal output signal A can be provided. Diagram III shows an example of further signal shaping, where, in addition to filtering by means of the filter element of the transmission mechanism 30, a modulation (in particular as "smoothing") is also caused by the driver 50.1 and / or the drive component 50.6. In this case, the input signal E deviates from the initial rectangular shape and, due to the modulation, shows an amplitude of the individual pulses that rises and then falls over time. For example, further signal shaping can be caused directly by the driver 50.1 when the input signal E is generated. Diagram IV shows an improved solution, in which a further modulation is used in addition to the modulation according to III. Here, the input signal E has a step shape, which may facilitate filtering by means of the transmission mechanism 30. In other words, according to diagram III, the drive component 50.6 and / or the driver 50.1 can be designed to perform the shaping of the input signal E by generating a rectangular signal with pulses that follow one another in time, where the pulse amplitudes of the different pulses vary over time, preferably with an amplitude that first increases and then decreases over time (especially within a pulse train), where the pulse amplitudes of the individual pulses are preferably (essentially) kept constant within the pulse width. In diagram IV, the pulse amplitudes of the individual pulses can also additionally vary over time within the pulse width, preferably with a step shape. In this way, a sinusoidal output signal A can be generated very reliably.

[0080] A particularly advantageous example of input signal E is shown in diagram V. This signal can be obtained, for example, by the following signal shaping, which is provided by driver 50.1 and / or driver component 50.6. For this purpose, driver component 50.6 is designed, for example, as a programmable voltage divider. The shape shown has a plurality of rectangular pulses that are sequentially connected in time, which differ from each other in pulse amplitude. For this purpose, for driver component 50.6, a drive signal can be output by driver 50.1 through different wires that are respectively connected to at least one resistor of driver component 50.6. It is designed, for example, in the form of pulse width modulation and is different for different wires. The resistance of different wires is, for example, of different sizes. In this way, input signal E can be generated very accurately in the desired shape. A particularly advantageous spectrum can be generated by shape symmetry, in particular by having the same pulse sequence that rises first and then falls, and / or by having the same absolute value of the amplitude difference for different pulses. In particular, the third harmonic in the spectrum of input signal E can be eliminated (perhaps completely) thereby.

[0081] The above description of the embodiments describes the invention only within the scope of examples. It is obvious that the individual features of the embodiments can be combined with one another freely as long as it makes technical sense without departing from the scope of the invention.

[0082] Reference numerals list

[0083] 1 Vehicle

[0084] 2 Trunk lid

[0085] 3 Bumper

[0086] 4. Door handles

[0087] 8 Users

[0088] 9 Body Parts, Activating Agents

[0089] 10 Components, circuit components

[0090] 20 Sensor mechanism

[0091] 20.1 Sensor electrode, sensor element

[0092] 20.2 Ground Potential

[0093] 30 Transmission mechanism

[0094] 30.1 Input

[0095] 30.2 Output

[0096] 30.3 Source mechanism, voltage source mechanism

[0097] 30.4 The first filter element, RC circuit for first-order low-pass filtering

[0098] 30.5 Second filter element, other components for 2nd order low pass filtering

[0099] 40 Input signal source, digital signal generation

[0100] 50 Controller

[0101] 50.1 Driver, Microcontroller

[0102] 50.2 Analog-to-Digital Converters

[0103] 50.3 Adjustment mechanism, software

[0104] 50.4 Holding mechanism

[0105] 50.5 Low-pass filter

[0106] 50.6 Drive Components

[0107] 50.7 Other Controls

[0108] 60 Switch mechanism

[0109] 80 pre-selector, pre-filter

[0110] 80.1 First terminal, power supply terminal

[0111] 80.2 Second terminal, ground terminal

[0112] r Receive path

[0113] t Send path

[0114] A Output signal

[0115] C Capacitor

[0116] CH Holding Capacitor

[0117] CS Sensor Capacitance

[0118] E Input signal

[0119] OP Operational Amplifier

[0120] R Resistance

[0121] S Switching element

[0122] U1 First Voltage

[0123] U2 Second voltage

[0124] VC supply voltage, second potential

[0125] VE supply voltage, first potential

Claims

1. An assembly (10) of a capacitive sensor mechanism (20) for a vehicle (1), comprising: - at least one sensor electrode (20.1) for detecting changes in the environment of the vehicle (1), a transmission mechanism (30) by means of which a frequency-dependent transformation of the electrical input signal (E) is performed in order to provide an output signal (A), - an output end (30.2) of the transmission mechanism (30), the output end (30.2) being electrically connected to the sensor electrode (20.1) to drive the sensor electrode (20.1) with the output signal (A), in, The transmission mechanism (30) has at least one filter element (30.4, 30.5) to perform the frequency-dependent change, wherein an input signal source (40) is connected to an input terminal (30.1) of the transmission mechanism (30) to provide an electrical input signal (E) in the form of a signal based on a rectangular signal at the input terminal (30.1), wherein the electrical input signal (E) is actively changed by the input signal source (40) to assist the frequency-dependent change of the transmission mechanism (30).

2. The assembly (10) according to claim 1, characterized in that The transmission device (30) is designed as an active electronic filter by means of the at least one filter element (30.4, 30.5).

3. The assembly (10) according to claim 1 or 2, characterized in that The transmission device (30) forms a low-pass filter by means of the at least one filter element (30.4, 30.5) in order to filter the electrical input signal (E) in such a way that at least radiation in the interference frequency range is reduced when the sensor electrode (20.1) is driven.

4. The assembly (10) according to claim 1 or 2, characterized in that The at least one filter element (30.4, 30.5) comprises a first filter element (30.4) and a second filter element (30.5), wherein the filter elements (30.4, 30.5) are connected to one another to jointly perform a frequency-dependent modification of the electrical input signal (E).

5. The assembly (10) according to claim 1 or 2, characterized in that The output signal (A) can be provided in dependence on a frequency-dependent change of the electrical input signal (E) in such a way that the at least one filter element (30.4, 30.5) is connected between an output (30.2) and an input (30.1) of the transmission mechanism (30).

6. The assembly (10) according to claim 1 or 2, characterized in that The input signal source (40) provides an electrical input signal (E) in the form of a signal based on a rectangular signal at the input end (30.1), the electrical input signal (E) being actively changed by signal shaping, by smoothing of the rectangular signal edges and / or by a time-variable amplitude to assist in frequency-dependent changes of the transmission mechanism (30), wherein the frequency-dependent changes include harmonic suppression.

7. The assembly (10) according to claim 1, characterized in that As part of the input signal source (40), a driver (50.1) is provided for generating the electrical input signal (E).

8. The assembly (10) according to claim 7, characterized in that As a part of the input signal source (40), a driving component (50.6) is provided for signal shaping of the electric input signal (E); the driving component (50.6) is connected between the input end (30.1) of the transmission mechanism (30) and the driver (50.1) so as to change the electric input signal (E) generated by the driver (50.1) through the signal shaping and load it onto the input end (30.1) of the transmission mechanism (30).

9. The assembly (10) according to claim 1 or 2, characterized in that A driver (50.1) as part of the input signal source (40) is designed to control a drive component (50.6) in the following manner: the electrical input signal (E) corresponds to a rectangular signal that changes between a first value and a second value, wherein the first value and the second value change over time in a manner that first increases and then decreases.

10. The assembly (10) according to claim 1 or 2, characterized in that A switching element (S) is connected between an output end (30.2) of the transmission mechanism (30) and the sensor electrode (20.1) so as to controllably connect a receiving path (r) and a transmitting path (t) to the sensor electrode (20.1) in turn, wherein the output end (30.2) is connected to the transmitting path (t) and a holding mechanism (50.4) is connected to the receiving path (r) for evaluation at the sensor mechanism (20).

11. The assembly (10) according to claim 1, characterized in that For evaluation at the sensor device (20), a holding device (50.4) is integrated in the receiving path (r) in order to receive a receiving signal after the sensor electrode (20.1) has been charged by the output signal (A) based on the charge stored in the sensor electrode (20.1) and / or based on a variable sensor capacitance (CS) of the sensor device (20), wherein the sensor electrode (20.1) is designed to provide the sensor capacitance (CS).

12. The assembly (10) according to claim 1 or 2, characterized in that The sensor electrode (20.1) is designed to be effectively electrically connected to the environment of the vehicle (1), so that when the sensor electrode (20.1) is driven, an electric field appears in the environment to provide a variable sensor capacitance (CS) according to the environment.

13. The assembly (10) according to claim 11, characterized in that A holding device (50.4) is provided for evaluating a variable sensor capacitance (CS) in order to detect changes in the environment of the vehicle (1) based on the evaluation, wherein the holding device (50.4) is designed as an integrator in order to perform charge accumulation based on the charge stored in the sensor electrode (20.1).

14. The assembly (10) according to claim 11, characterized in that The transmission mechanism (30) is connected to the holding mechanism (50.4) to receive a reception signal from the sensor electrode (20.1) at the holding mechanism (50.4) according to a change in frequency.

15. The assembly (10) according to claim 11, characterized in that The operational amplifier input of the transmission mechanism (30) is connected to an integrator input of the holding mechanism (50.4) so ​​as to receive a reception signal from the sensor electrode (20.1) according to a frequency-dependent change, so that the frequency-dependent change is provided not only for the reception signal in the reception path (r) but also for the output signal (A) in the transmission path (t).

16. The assembly (10) according to claim 1 or 2, characterized in that The transmission mechanism (30) forms a filter with low-pass filtering performance, which has a limit frequency of 100 kHz to 800 kHz.

17. An exterior door handle (4) for a vehicle (1) having an assembly (10) according to one of claims 1 to 16.

18. A method for operating a capacitive sensor arrangement (20) of a vehicle (1), wherein: The sensor device (20) has at least one sensor electrode (20.1) for providing a sensor capacitance (CS), wherein the following steps are performed: a) switching at least one switching element (S) to connect the transmission path (t) to the sensor electrode (20.1), b) generating an electrical input signal (E), c) performing a frequency-dependent transformation of the electrical input signal (E) to provide an output signal (A), d) outputting the output signal (A) at the sensor electrode (20.1) via the transmission path (t), e) switching the at least one switching element (S) in order to connect the receiving path (r) to the sensor electrode (20.1) and in order to remove the connection to the transmitting path (t), f) transmitting a received signal from the sensor electrode (20.1) to a holding device (50.4) in the receiving path (r) in order to evaluate the sensor capacitance (CS).

19. The method according to claim 18, characterized in that: As a result of the frequency-dependent change, harmonic suppression is achieved both in the output signal (A) and in the received signal.

20. The method according to claim 18 or 19, characterized in that: The generation of the electrical input signal (E) is repeatedly interrupted in a periodic signal manner to provide an interruption phase to suspend the output of the output signal (A).

21. The method according to claim 18 or 19, characterized in that: The assembly (10) according to one of claims 1 to 16 can be driven.

Images